passive house +

editor’s lettern the years to come, I suspect we’ll look back on Wednesday 9 January 2013 as oneof the defining dates in Ireland’s transition to a low energy nation. From that day on, anykind of advert for the sale or rental of a house, flat, office or factory must include theBuilding Energy Rating (BER) score. Though this may seem like a fairly innocuouschange – after all, BERs have been mandatory at the point of offer on any property

that’s up for sale or rent for four years already – its implications are profound.

Drafted in 2002, the defining idea behind the EU’s Energy Performance of Buildings Directive(EPBD) was to use energy ratings to move the market, the rationale being that consumerswould pay more or less for buildings based on their BER score, amongst other factors. Thelogic was sound, but the application let it down.

Ireland’s transposition of this requirement demanded the BER at the point of offer on a prop-erty. Although SEAI and the Department of the Environment insisted that the rating must beavailable at the point a property was put on the market, the property industry took a differentview, arguing that estate agents don’t offer property for sale or rent, but rather invite offersfrom interested parties. Often the rating was only handed over once a sale or letting had beenagreed (and in the rental market the requirement was often entirely ignored). This is clearly fartoo late to influence transactions.

In 2009, I proposed a solution to this problem that was accepted by the Fianna Fáil and GreenParty coalition for its renewed programme for government: display the BER score prominentlyin all property advertising, including everything from online and print media to for sale sig-nage. This means exposing people to the rating before they’ve looked at a photo or set footacross the threshold – before they’ve had a chance to form an opinion about the building.

This change is bound to mean that BERs will become a central factor in how quickly a build-ing transacts – and in the price it fetches. It's also bound to drive the construction of newhomes and upgrading of existing homes. New homes must typically meet a mid-range A3BER to comply with stringent new building regulations, and will therefore gain a competitiveadvantage over the less efficient existing housing stock – which in turn will drive more peopleto aim for ambitious energy upgrades.

As it turned out the EU recast the EPBD in 2010, including a requirement that energy ratingsbe included in advertisements in commercial media. Although this term was open to interpre-tation, the requirement in the programme for government requirement had set the officials inSEAI and the Department of the Environment on a path towards a more ambitious transposi-tion. They deserve great credit for their work.

I have to finish by mentioning the elephant in the room: from this issue on, Passive House Pluswill be published in separate Irish and UK editions. Much of the content will be shared be-tween the two editions. This is most manifestly obvious in the six case studies in this issue,divided equally between exemplary Irish and UK buildings. We hope you enjoy this new ap-proach. We believe it’s a unique opportunity for two construction industries with similar cli-mates, regulatory environments and construction cultures to learn from each other, work witheach other, and inspire each other towards advances in sustainable building.

Regards,the editor

I

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ABC Certified Average Net Circulation of 7,223for the period 01/07/11 to 30/06/12

(Under the former title of Construct Ireland)

I2 V1

PUBLISHERS: Temple Media Ltd.PO Box 9688, Blackrock, Co. Dublin, Ireland

T: +353 (0)1 2107513 / +353 (0)1 2107512Email: [email protected]

www.passivehouseplus.ie

EDITORIAL

EDITOR: Jeff ColleyE: [email protected]

DEPUTY EDITOR:Lenny AntonelliE: [email protected]

REPORTER:John HearneE: [email protected]

CONTRIBUTORSSofie Pelsmakers, Architecture for Change

Nick Grant, The Passivhaus Trust Jonathan Hines, Architype

Sam Mays, Fitzpatrick & MaysJoseph Little, Joseph Little Architects

IT / WEBSITE

Dudley ColleyE: [email protected]

ACCOUNTS

Oisin HartE: [email protected]

ART DIRECTOR

Lauren ColleyE: [email protected]

PRINTING: W&G Baird, T: 048 9446 3911

www.wgbaird.com

Publisher’s circulation statement: 12,000 copiesof Passive House Plus are printed and distributed tothe leading figures involved in sustainable building inIreland including architects; consulting, m&e andbuilding services engineers; developers; builders;energy auditors; renewable energy companies; en-vironmental consultants; county, city and town council-lors; key local authority personnel; and to newsagentsnationwide via Easons.

Disclaimer: The opinions expressed in PassiveHouse Plus are those of the authors and do notnecessarily reflect the views of the publishers.

Cover: PlummerswoodPhotograph: Sandy Halliday

2012 Business magazine of the year - Irish Magazine Awards

Jeff Colley:

winner - green leader award - Green Awards 2010

Construct Ireland:

winner - green communications award - Green Awards 2010

WINNERGreen Leader Award

WINNERGreen Communications Award

Passive House Plus (Irish edition) is the official magazineof Éasca and the Passive House Association of Ireland

cont

ents

6 NEWS

22 BUILDING OR UPGRADING?

Passive House Plus is here to help make your building more sustainable

24 COMMENT

28 INTERNATIONAL

Nothing drives innovation like adversity. Facing up to the prospect of scarceenergy and other resources, we can take inspiration equally from the Inuitand the most avant-garde of passive house designers, as Sofie Pelsmakers

reveals in her choice of six uniquely inspiring buildings from around the world.

38 NEW BUILD

38 Ireland’s most energy efficient building?

A new house in Wexford is the first in the country to achieve anA1 Building Energy Rating and certified passive house status –arguably making it the most energy efficient building yet built inIreland. So why did a regulatory flaw risk rendering it non-compliant?

46 Scottish Borders home mixes ecology & efficiency

A stunning location, thoughtful design and a certified passivehouse: a new home in the wooded hills of the Scottish Bordersmanages to have its cake and eat it too.

54 Wicklow house comes close to passive

With a target as exacting as the passive house standard, circum-stances can conspire against meeting every criteria. ArchitectSam Mays describes a Co Wicklow home where the builderwent bust, leaving a striking building that hit every passive targetbar one.

60 Sustainability centre with a passive message

One of the UK’s first non-domestic buildings to gain passive housecertification, the Simmonds Mills designed Green Base centreis an embodiment of the environmental ethos it seeks to promote.

66 UPGRADE

66 Monkstown semi-D sets deep retrofit example

A house in south Dublin recently became the first Irish buildingto become Enerphit certified. Architect Joseph Little describesthe challenges of meeting the Passive House Institute’s standardfor upgrading existing building.

74 Islington centre gets award-winning passive upgrade

A community centre in a deprived area of north London hasbecome one of the few buildings in the UK & Ireland to get passivehouse certification with a renovation.

82 INSIGHT

82 How to rescue retrofit

Progress on retrofitting Europe's building stock is sluggish, butthere is a way out of the mire.

87 The passive house in a warming world

The coming decades are expected to bring higher averagetemperatures, more extreme weather events – and possiblymore cold snaps. But how are passive house buildings gearedto adapt to a changing climate?

89 GLOSSARY

Perplexed by all this talk of U-values, blower-door tests and embodied en-ergy? Our sustainable building glossary will help you get to grips with thekey terminology

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passivehouse+ | Issue 2 Volume 1

News

Passive House Plus wins businessmagazine of the year awardWe’re delighted to announce that Passive HousePlus has won the business magazine of theyear award at the 2012 Irish Magazine Awards.

The judges of the awards – which were an-nounced at a swanky event at Dublin’s ClydeCourt Hotel in December – cited the maga-zine’s "high editorial and design standards”and “commitment to audience engagement”.

Passive House Plus pipped some stiff com-petition to win the gong. Finalists vying for thelarge circulation Business to Business Maga-zine of the Year award (for publications withcirculation above 5000 copies) included Busi-ness Plus, Euro Times, the Law Society Gazetteand the Engineers Journal.

“This kind of recognition means a great dealto us – It's an amazing endorsement of ourdecision to rebrand from Construct Ireland toPassive House Plus and expand into the UK,”said Passive House Plus editor Jeff Colley. “Amassive thanks to all our subscribers, adver-tisers and contributors. Without your loyalty,we'd be nothing.”

The magazine’s rebrand and expansion proj-ect also saw Passive House Plus nominatedunder the innovation of the year category, withColley nominated for business magazine editorof the year.

Any sale or rental adverts for Irish propertiesthat don't display Building Energy Rating scoresare breaking the law, as a result of new reg-ulations introduced on 9 January.

The game-changing new policy – which PassiveHouse Plus editor Jeff Colley successfullylobbied to include in the Fianna Fáil/GreenParty coalition's renewed programme for gov-ernment in 2009 – means that BER scoresmust be included wherever a building is ad-vertised for sale or to let in Ireland. The policyincludes everything from print and online ad-verts and listings, to estate agent windows,sales brochures and for sale/to let signs.

Coincidentally, following Colley's lobbying in2009, a similar but less specific proposal wasincluded in the recast EU Directive on the En-ergy Performance of Buildings in 2010, with astipulation that an indicator of a building's en-ergy rating must be included in advertising incommercial media.

Building control authorities are responsible forenforcing the new requirements, which also applyto all properties that were put on the marketbefore 9 January. People selling properties –or agents acting on their behalf – may be subject

to fines of up to €5,000 or prison sentences ofup to three months if they fail to comply.

Speaking to Passive House Plus, MyHome.ieMD Angela Keegan said: “we welcome the moveand we believe it will help to educate consumersas to the importance of a good energy ratingand the associated benefits.”

One of the two largest online property portalsin Ireland along with Daft.ie, MyHome.ie tookaction to prepare its site for energy ratings inadvance of the new law coming in while its rivalhas been slower to respond. But at the timeof writing, less than 10% of the ratings on My-Home.ie list BERs. “On a daily basis we‘re see-ing more ratings being added to MyHome.ie,”said Keegan. “I think it will take an amount oftime before all properties carry a rating. I wouldexpect to see all new properties coming to themarket complying with the regulation.”

Keegan predicts that over time BERs willhave an impact on property prices. “I think asthe home-buying public become more awareof the benefits of an energy efficient home itwill come into the negotiation on price,” she said.

A spokesperson for the Society of Chartered

Surveyors Ireland – the body created as a re-sult of a merger between the Society of Char-tered Surveyors (SCS) and the Irish Auctioneers& Valuers Institute – welcomed the news.

“The more information that purchasers haveabout buildings, the better, because it helps themto make informed decisions,” the spokesper-son said. “If people have access to the BERdata early in the search that's a good thing.”

(above) Listings on MyHome.ie are starting to complywith the requirement to display BER scores for eachproperty

Energy rating ad law to transform Irish property market

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(above) Pictured at the Irish Magazine Awards are Passive House Plus editor Jeff Colley and Magazines Irelandchief executive Grace Aungier


News

Second Better Building conference to be heldat Croke ParkThe second Better Building conference is tobe held on 24 April in the Croke Park conferencecentre, Dublin. The inaugural conference at RoyalHospital Kilmainham last year sold out withnearly 400 attendees.

"Better Building has become the must attendevent in the calendar for anyone involved in theproperty or construction sector," said IGBC Di-rector Pat Barry.

The conference will tie in with the Irish Pres-idency of the EU and will bring an increasedEuropean perspective with announcementsexpected regarding retrofit funding from Europe.

Delegates can tailor their conference from anumber of simultaneous streams. "The vast rangeof sessions with outstanding speakers makes theconference unmissable, whether you are a propertyinvestor or a passive house designer," said Barry.

Barry said the event is aiming to "showcasesome of the world class research taking placein Irish universities and research centres, par-ticularly where it involves partnership with in-digenous Irish companies" as well as "outstandingdeep retrofit case studies". Substantial discountsare available for those who book early atwww.betterbuilding.ie

Better Building is organised by the Irish GreenBuilding Council, Cultivate and the Sustain-able Building Show, in partnership with En-terprise Ireland and in association with Ecocem,the low carbon cement supplier.

Croke Park, the venue for the conference, isthe first stadium in the world to be awarded thecoveted BS 8901 accreditation for sustainableevent management due to its "considerable"reductions to energy and water use since start-ing their sustainability programme in 2008.

(above) Renovate Europe campaign director Adrian Joycespeaking at the inaugural Better Building conference

The Passive House Institute has announcedthat it certified 134 products last year, a newrecord. These components included everythingfrom sliding doors and dome lights to balconysystems.

The institute presented certificates for a range ofnew products at the BAU 2013 trade fair inMunich in January.

"Anyone building a passive house today hasa wide range of high quality products to choosefrom," said Professor Wolfgang Feist, directorof the institute. He said that in the past few years,pioneers in the market have improved theirproducts and simplified their application, andnew suppliers have entered the market too.

"As a result, a great variety of building com-ponents required for passive house are nowavailable and, in many cases, these compo-nents have become cheaper."

At the end of 2012 passive house designerscould choose from over 100 certified ventilationunits and nearly 100 window frames.

As an independent authority, the Passive HouseInstitute tests and certifies products with regardto their suitability for use in passive housebuildings. The institute said that its certificationguarantees "the highest standard of thermalcomfort when used in any energy efficientbuilding".

At the BAU trade fair in Munich, certificateswere presented to companies including SchöckBauteile for thermal insulation, Schüco fortheir curtain wall facade, Raico Bautechnikfor their aluminium window frame and Schiedelfor their extract air system.

(above) Prof Wolfgang Feist has announced that thePassive House Institute certified 134 products in 2012

Record number of products getpassive house certification

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Must read - The Passivhaus HandbookThe Passivhaus Handbook – A Practical Guideto Constructing and Refurbishing Buildingsfor Ultra-Low-Energy Performance is an es-sential guide for anyone interested in thepassive house approach to building or up-grading.

Written by UK passive house pioneers JanetCotterell and Adam Dadeby, the PassivhausHandbook will be of benefit to anyone look-ing to build an extension, upgrading or start-ing from scratch. Bringing together currentthinking and best practice on passive house,this book will help you navigate around thepotential pitfalls and misconceptions, and willbe a key reference for everyone from greenminded homeowners to experienced passivehouse designers.

The book can be purchased via www.green-books.co.uk


News

Glen Dimplex launches "revolutionary"thermal storage system

Glen Dimplex has developed a "thermal stor-age invention", dubbed Quantum, that it expectsto "revolutionise home heating systems worldwide".The company said the system is the first ofits kind and will revolutionise the way energycompanies charge storage heaters whilst max-imising use of renewable wind energy.

Glen Dimplex described it as the most signif-icant development in the history of the com-pany, and said it would help maximise the useof renewable wind energy and significantly re-duce carbon emissions.

With an estimated seven million storageheaters in Ireland and the UK, Glen Dimplexsaid that the invention is a "21st century tech-nological advancement" of the night storageconcept that was developed in the 1950s.

The Quantum heaters are designed to storeenergy that is produced by wind turbines at offpeak times, then release it when it is needed.They can also communicate with the nationalgrid and electricity suppliers, so can be triggeredto store surplus power once it becomes available.

The product was developed in Ireland and willbe exported worldwide, the company said.

"Almost half of all Irish homes are fuelled byimported oil and so this new system will givethe ordinary homeowners and organisationslike housing associations a very attractive optionthat will reduce fuel bills, especially to lowerincome families and the elderly, and may helpremove them from fuel poverty," said Glen Dim-plex chief executive Sean O'Driscoll. "Overallthe project has the potential to become a

major new industry supporting many hundredsof new jobs at the group’s locations in the Re-public of Ireland and Northern Ireland."

A pilot project with 140 homes at two locationsin Dublin is already underway in partnershipwith the Green Way, Dublin's cleantech clus-ter organisation. Glen Dimplex said the proj-ect has already shown that Quantum has thepotential to deliver a 30% economic saving toindividual homeowners (or €264 saving perhome) as well as a 15% energy saving.

Quantum is expected to be extended to over1,000 homes in Ireland next year as well as to 100homes with the Northern Ireland Housing Executive.

(above) Glen Dimplex chairman and CEO Sean O'Driscollwith founder Martin Naughton at the launch of Quantum

The Heat Pump Association (HPA) of Irelandis now affiliated to the European Heat PumpAssociation, the HPA has announced.

The move follows a recent visit by represen-tatives of the European organisation to Ire-land to discuss the inclusion of heat pumptechnology in coursework at Galway Mayo In-stitute of Technology, during which represen-tatives of both organisations met.

Following that, members of the HPA visitedBrussels for a meeting of national heat pumporganisations from across Europe to ex-change ideas and information. The keynote

speech at the event was delivered by Joe Durkanof the Sustainable Energy Authority of Ireland.

Durkan outlined SEAI's vision for heat pumpsin the future of energy management in Ireland.While the electricity grid could become unstablewith much extra wind power without further upgradeto its infrastructure, heat pumps can help to smooththe load by using wind power to heat buildings.

While in Brussels, the HPA also met with IrishMEP Sean Kelly. "We discussed our aspirationsfor heat pump technology and how it wouldbe included in smart rural energy for Ireland,"a HPA spokesperson said, adding that Kelly's

response was highly positive. Kelly invited theHPA to speak at an upcoming energy awarenessevent to be held in his Munster constituency aspart of Ireland's presidency of the European Union.

Companies that are members of the HPA willalso soon be able to add their reference proj-ects to a Europe-wide interactive map of sus-tainable technologies at repowermap.org, aninitiative supported by Intelligent Energy Europe.

The HPA will be also giving a presentation at theEuropean Conference on Renewable Heatingand Cooling, which is taking place in Dublin on22 to 23 April.

Heat Pump Association gets European affiliation

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News

Open up to smart energy solutionsat the SEAI Energy ShowThe Sustainable Energy Authority of Ireland’sEnergy Show 2013 will take place at the RDSin Dublin on Wednesday 10 and Thursday 11April. SEAI said the annual two-day businessevent is the "key energy showcase in the Irishcalendar – a must for those who want to be upto speed on the latest energy saving solutions".

"Open up to smart energy solutions" is thetheme of the show, which will focus on therange of opportunities for businesses in en-ergy efficient and renewable energy solu-tions. The trade exhibition will present leadingsuppliers of sustainable energy products andservices in Ireland, including the latest solu-tions available for those in the constructionand energy management sector.

In addition, the seminar programme will addressthe most current and topical developments facingthe sector both nationally and internationally.

The seminar 'Towards nearly zero energybuildings' will be of particular interest to thoseworking in the building and retrofit industry.

This seminar will focus on the regulatory, designand construction changes required for nearlyzero energy buildings. Speakers will includeDavid Brennan from BDP, who will discuss

the transformation of old urban buildings intonearly zero energy buildings, and Sean Arm-strong of the Department of the Environment,who will speak about the future regulatoryframework for such buildings.

There will also be a seminar detailing signifi-cant projects by large energy users.

The seminars will aim to provide "practical ad-vice to all those attending, as well as providingarchitects and construction industry profes-

sionals the opportunity to network, share ideasand discuss information with their peers".

The free exhibition will run on Wednesday 10April from 10am to 6pm and on Thursday, 11April from 10am to 6pm. Seminar places mustbe pre-booked in advance with a limited numberof spaces available. For further details visitwww.seai.ie/energyshow.

(above) The Energy Show 2012 at Dublin’s RDS

Heliotherm have come out on top of a recenttest carried out on 46 different heat pump in-stallations across Europe with an annual COPof 7.29.

The EU-funded Sepemo project, standing forseasonal performance and monitoring, wasset up to gather information on the real lifeperformance and reliability of heat pumps in

the field on a day-to-day basis and was carriedout by the Austrian Institute of Technology.Forty-six heat pumps were tested across sixEuropean countries.

The AIT certified Heliotherm not only with an"unusually high ACOP" (annual coefficient ofperformance), but also noted that the heatpump ran error free during the testing period.

"The result really didn’t come as a surprise tous,” said Brian Cooley of Climate Control Re-newables Ltd, Heliotherm's installation partnerin Ireland. “We’ve been seeing similar per-formance figures and running costs since webegan installing Heliotherm heat pumps in2004, but it is nice to see the fact being inde-pendently recognised by an impartial body, assometimes it can be hard for customers tosee it as anything other than a sales pitch.

"The performance of the system and the reli-ability is a testament to Heliotherm's philoso-phy of having approved installation partnerswith a common methodology of installation anda complete understanding of how differentfactors influence the entire system,” Cooley said.“It produces high performance systems timeafter time.”

There are over 300 Heliotherm heat pumpsoperating in Ireland at the present time andover 25,000 installations Europe-wide. Thecompany produces heat pumps ranging from6kW to 500kW in both ground source and air-to-water units. Heliotherm partners can "guideyou through the entire lifetime of your systemfrom design through to installation and service".

(above) The house where a Heliotherm heat pump(inset) was tested as part of the Sepemo project

Heliotherm achieve COP of 7.29 in heat pump test

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News

Ireland to host European fuel povertyConference in March

Irish charity Energy Action will host the Euro-pean Fuel Poverty Conference in Dublin on11 and 12 March.

This conference is the first of its kind, andbrings together fuel poverty researchers, pol-icymakers, and practitioners from all over Eu-rope, in order to "seek areas of commonground and shared understanding".

It is estimated that 65 million Europeans livein fuel poverty, which is associated with morethan 30,000 excess winter deaths in Europe

per year.

Energy Action said that despite fuel povertybeing an enduring concept with widespreadimpact, there is no European consensus asto how it should be defined, or how to meas-ure or monitor it. Consequently, there is nocommon European strategy for tackling it,and Europe-wide perspectives remain "im-mature and disjointed".

The charity said that in the current context ofeconomic crisis, the number of households in

fuel poverty is set to continue increasing at arapid rate. The conference is designed to fa-cilitate enhanced communication betweenstakeholder groups with a view to tacklingand preventing it across Europe.

The keynote address at the event, titled 'TheState of the Problem', will be jointly deliveredby Professor Brenda Boardman of the Envi-ronmental Change Institute at Oxford Univer-sity, Professor Christine Liddell of the Universityof Ulster, and Professor Sharon Turner of Queen'sUniversity.

Energy minister Pat Rabbitte and Nelson Mc-Causland, Northern Ireland's minister for socialdevelopment, will jointly launch the conference.

The event will aim to build areas of consensus,raise the profile of fuel poverty, and seek "waysof embedding energy poverty within the broaderrubric of EU legislation and remedial action".

It will also aim to facilitate dialogue betweenpolicy makers, regulators, local authorities, is-land communities, politicians, health experts,researchers, private contractors, energy com-panies and the various agencies supportingvulnerable people in Ireland and Europe.

Energy Action will also provide exhibition spaceat the conference venue and welcomes en-quiries from businesses wishing to exhibit atthe event.

Energy Action has organised the last two Na-tional Fuel Poverty Conferences in Dublin Castle.

For further information on the conference,contact [email protected] or visitwww.energyaction.ie

(above) Professor Christine Liddell speaking at EnergyAction’s National Fuel Poverty Conference in 2012

Local authorities throughout the country haveincluded an option to request 'low carbon'concrete products in the tender process fortheir construction projects.

“The introduction of low carbon cement in thelocal authority tendering process is one of thesingle biggest advancements in Ireland’s greenerprocurement policies," said David O'Flynn ofIrish low carbon cement supplier Ecocem. "Itwill go a long way towards helping Irelandmeet its Kyoto commitments and will positionIreland as an example for other European coun-tries to follow going forward.”

The new tendering framework, which came intoeffect on 1 January, applies to 33 local au-

thorities throughout the country, the only ex-ception being Dublin City Council, who operate aseparate but similar tendering process.

Cement production is one of Ireland's singlelargest industrial sources of carbon emissions.However, Ecocem said that concrete madewith low carbon cement can achieve savingsof up to 500,000 tons of CO2 emissions an-nually in Ireland.

The introduction of the option of low carbonready mix concrete in the document ‘Instruc-tion to Contractors/Suppliers – Ready Mix &Concrete Additives 2013/2014’ means thatlocal authority engineers and architects cannow choose the option of low carbon concrete.

Ecocem said that low carbon concrete is strongerthan regular concrete, offering greater resist-ance from factors such as fire, de-icing salts,acids and sulphate attack, such as found onwater and wastewater projects, offices, foot-paths, roads or in marine environments.

Its lighter in colour appearance also makes itbrighter looking than regular concrete as canbe seen in high profile structures such as theAviva Stadium, and the Boyne and Suir cable-stayed bridges.

Ecocem are also currently offering €3,000worth of low carbon concrete in a competition— anyone interested in entering should visitlowcarbonconcrete.ie.

Local authorities open the door to low carbon concrete

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News

Isover dry lining gets NSAI approvalIsover has announced that its Optima systemhas become the first dry lining system approvedby the National Standards Authority of Ireland.

Isover said this means it has been "testedand approved to not only improve the thermaland acoustic performance of a building, but it’sunique in that it also takes care of potentialmoisture issues and helps to reduce thermalbridges normally associated with dry lining".

Optima is "a high performance renovation so-lution for insulating older houses from the inside,"the company said.

Isover added that Optima had been developedto improve thermal and acoustic performancewhere cavity wall or external insulation is in-sufficient, or not an option.

The company said that Optima offers a "sim-ple solution for the quarter of a million solidbrick houses currently in Ireland, as well asmany more cavity wall homes".

The average residential home can experienceup to 30% heat loss through external walls.

Isover Ireland is part of the Saint-Gobaingroup. The company said that at the "heart ofour strategy is the promotion of best practicein renovation solutions and driving buildingstandards improvements".

The company added that it aims to create"healthy buildings and living environments forresidential home-owners — warmer, morecomfortable homes, acoustically improvedand with reduced energy costs."

Isover is also offering free training to installers

and contractors on the new Optima dry lining& air tightness solutions at their "state of theart" technical academy in Kingscourt, Co Cavan.

Pictured are: (left to right) NSAI Agrément director SeanBalfe with Gyproc and Isover Ireland MD Brian Dolan

Ashgrove Renewables has signed a contractwith Swedish heat pump manufacturer Ther-mia to represent them in Ireland and North-ern Ireland. According to Ashgrove, Thermia’sAtec heat pumps have been awarded "bestin test" in Scandinavia, giving them the highestannual efficiency of ten air to water heat pumpstested by the Swedish Energy Agency in 2011.

Ashgrove is also planning a series of free na-tionwide open days for self-builders and home-owners, as well as architects, engineers, plumbersand other members of the trade. "The purposeof these open information days is to dispelsome of the ambiguity, myths, and precon-ceptions about the benefits and pitfalls of re-newable energy," said Ashgrove managingdirector Shane Murphy.

He added that the company wants to provide"as much concise information and clarity aspossible to a field which has become cloudedby bad advice and misinformation."

"Most people are confused and worried aboutwhat might be the most suitable technologyfor them and their project," he said. "There’s so

much conflicting information in this industryit’s hard to distinguish good from bad advice."

Ashgrove recently completed a number of tech-

nical studies on completed projects whichMurphy said had returned "some very inter-esting results". The company then presentedits findings at a series of free public events.

Ashgrove said the findings of their researchand consultations led the company to com-pletely revamp its product line to better suitthe needs of its customers.

"Last year was a very exciting one and pre-sented many unique opportunities for Ash-grove," Murphy said.

“Last year the Heat Pump Association of Ire-land confirmed that we supplied 10% of allheat pumps installed in Ireland for 2011."

Ashgrove Renewables was established in1994. The company said that in that time ithas been designing, installing, and testing arange of bespoke renewable energy solutionsfor a wide variety of applications.

(left) The Thermia Atec heat pump, which wasawarded “best in test” out of ten air to water heatpumps tested by the Swedish Energy Agency in 2011

Ashgrove Renewables announce newproduct range for 2013

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News

Green solutions the focus of German building services fair

ISH 2013, the "world's leading trade fair" forbathrooms, building services, energy, air con-ditioning technology and renewable energies,will take place in Frankfurt from 12 to 16March. The event is organised by Messe

Frankfurt and will be hosted at the FrankfurtFair and Exhibition Centre.

The ISH energy section will focus on efficientheating systems and renewable energies, as

well as achieving energy efficiency and comfortwith ventilation and air conditioning technology.

The water section will "spotlight the way wateris used and set new accents with regard todrinking-water treatment and sustainability".

Over 2,300 exhibitors and 200,000 visitorsare expected to attend the event.

The sanitation, heating and air conditioninginstallation trade will make up the largest groupof visitors.

Visitors will also have the opportunity to take partin over 30 workshops and lectures revolving aroundthe subject of "holistic bathroom planning".

Air conditioning, cooling and ventilation tech-nology will feature in the Aircontec section ofthe exhibit. The industry will present "innova-tive components and systems that, besides ahigh degree of energy efficiency, ensure ther-mal comfort and high-quality indoor air".

“Resource conservation is the subject aroundwhich everything at ISH 2013 revolves – with-out neglecting comfort and design”, said IrisJeglitza-Moshage, senior vice president ofMesse Frankfurt Exhibition.

(above) Visitors and sustainable energy exhibitorsmix at ISH 2012

Munster Joinery has launched its PassiveAluP window, which features a high perform-ance thermal break that allows the use of alu-minium on the inside and outside of thewindow while achieving passive levels of per-formance, the company said. Passive AluP hasbeen certified as a passive house suitable com-ponent by the Passive House Institute.

Aluminium has traditionally been a very popularwindow material because of its durability, lowmaintenance and structural properties. But likeother metals aluminium is a good conductor ofheat, so thermal breaks are used to insulate theinside of the window frame from the outside andprevent the loss of heat through the aluminium.

However, a maximum window U-value of 0.80W/m2K is allowed under the passive housestandard. This places demands on windowperformance that exceed what has beenachieved by conventional thermal breaks, soaluminium can typically only be used in passivehouse windows as an external cladding only.

However Munster Joinery have now devel-oped the Passive AluP window which thecompany said has "an extremely low con-ductivity insulating foam core combined with

effective isolation of internal aluminium fromexternal to give a thermally excellent frame".

The company said that the "detail of the designhas been fine-tuned at all critical points toeliminate thermal bridging".

This technology is combined with efficienttriple or quadruple glazing with multiple panesof low emissivity glass and cavities filled withargon or krypton gas. Edge losses are reduced toa minimum by the use of warm edge spacer bars.

The result is a window which, uniquely, "hasthe advantages of aluminium both inside andoutside and the thermal performance requiredfor passive and A-rated housing."

Munster Joinery said the window performswell on air permeability, watertightness, windresistance, operation and strength and securitytesting. It comes in a range of RAL coloursand is available in wood effect finishes.

"While achieving thermal excellence the win-dow remains a very practical functional windowwith the versatility to have aesthetic appeal,"the company said.

(left) Passive AluP, Munster Joinery’s new ther-mally broken window range with internal and ex-ternal aluminium cladding

Munster Joinery windows combine internal& external aluminium with thermal breaks

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Baumit to showcase "innovative" externalinsulation render at EcoBuildBaumit UK will be showcasing an "innovative"new external thermal insulation technologyon 5-7 March at EcoBuild 2013 in Excel, London.

The Baumit OPEN external wall insulation (EWI)system is a thin coat render system for solidwall construction.

Baumit said the system provides breathablethermal insulation, plus energy and cost sav-ings, and comes in a broad range of rendercolours and finishes. It also has self-cleaningproperties that increase the life span of theexternal finish, reducing costs in re-painting,the company said.

Baumit are now offering their portfolio of ex-ternal thermal insulation systems, façades andrenders to the UK market through their net-work of distributors and highly trained installers.

“Feedback from renovations and new buildswhere the revolutionary Baumit EWI systemhas been used has been very positive, withmany homeowners reporting considerableenergy and cost savings as well as a highlevel of improvement to the external façadeappearance,” said Sue Dewhirst, consultantwith Baumit UK.

The company said its "broad portfolio of EWIand rendering products provides a one-stop-shop for architects, builders, designers, andspecifiers aiming for improved energy andcost efficiencies, insulation properties andcompliance with Green Deal requirements."

Its portfolio of products also includes: BaumitStar Track (an insulation anchor fixing systemthat eliminates thermal bridging and is appli-cable to any existing surface); Baumit Life (acolour system featuring 888 façade colours);Baumit Profiles (a comprehensive range offaçade profiles for window, doors, cornersand other applications); Baumit NanoporTop(a low maintenance decorative finish based onnano-technology that provides a "breathableself-cleaning top coat for long lasting cleanli-ness and beauty for the façade"); and BaumitOpen Duplex, a remediation product for existing

thermal insulation systems.

Baumit said that throughout the temperatureand humidity changes that external walls ex-perience, the Baumit Open EWI system de-

livers stability, heat retention, fire protectionand sound insulation within the home.

(above) A low energy modernist house externally insulatedwith the Baumit system

Enterprise Ireland has awarded funding to a"representative grouping of construction andconstruction product companies" to examinethe potential opportunities outside of Irelandfor the construction of ultra low energy dwellings,and the opportunities to supply Irish productson such projects.

“This cluster group recognises that Ireland is inan advantageous position, spurred on by require-ments of the Energy Performance of BuildingsDirective and in particular adaptation of the pas-sive house standard out of Germany," said En-

terprise Ireland's Dr Paul Butler. "Ireland now findsitself in the enviable position of being the coun-try with the greatest number of professionalpassive building practitioners in the Englishspeaking world, with a sizeable number of Irishcompanies selling products into this market."

The cluster programme is in two phases. Thefirst phase will identify the opportunities thatIrish companies can take advantage of abroad.It will also begin developing a directory of ex-porting manufacturing companies and servicecompanies and finally examine the potential for

a 'campus' on which low energy or zero en-ergy buildings, together with related productsand technologies, can be showcased.

“Together with the reference companies, wehave commissioned Tomás O’Leary and MosArtto carry out the initial phase of the research,"said Butler. "This will inform us of where we needto go and what we need to do to achieve it. Byreinventing ourselves and being early adaptorsof the standards, Ireland’s construction sectorcan flourish again and bring much needed wealthback into the country."

Enterprise Ireland announces funding for low energy construction

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Hevac package plant room deliveredto Dublin hospitalHevac’s commercial and industrial divisionhas delivered one of its boiler house packageplant rooms for the HSE at St Mary’s Hospi-tal, Phoenix Park.

The plant room incorporates two De DietrichMCA 90 wall-hung gas boilers with Duomogas detection, Wilo pumps and pressurisationunit, and pipes and fittings all supplied fromHevac’s warehouse in Dublin.

The plant room was designed by Hevac’sown design and engineering team, who pro-duced AutoCAD drawings for client approvaland completed the entire design and buildprogram to the client’s specification.

Hevac said the advantages of a single com-plete delivery to site include reducing on-sitelabour, eliminating possible damage by othertrades and minimum downtime of plant. Theplant room design ensures a reduction in sitecost, disruption, and the use of premium sitespace, the company said.

Karl Carrick from Hevac commented that aspart of the company's "continued drive to bethe number one in the industry", they are con-stantly extending their offer. “The packageplant room is the obvious extension to thatoffer," he said.

More and more new build and refurbishmentprojects are being designed with pre-fabri-cated, off-site plant, which is more cost-effec-tive and arrives fully tested and ready for finalinstallation, Carrick said.

Hevac said that work on building the plantroom can commence in tandem with the mainconstruction and will be unaffected by on-site

influences such as weather, health and safetyissues and unforeseen disruption.

The company said that a construction site isfar from an ideal place to construct and installa plant room, and that the benefits of under-taking the work in a clean and dedicated fac-tory environment will result in a better qualityfinished plant room.

Hevac has 40 years experience in the industry,

and said its range of packaged plant rooms canincorporate various services including heatplant, hot water generation, pump rooms, genera-tor plant, water filtration, steam plant for heat-ing or process system, and combined heat andpower.

(above) The packaged plant room being deliveredcomplete with two De Dietrich wall hung boilers atSt Mary’s Hospital

Irish timber panel manufacturer SmartPly hasurged specifiers to think about sustainability whenchoosing wood panel products.

The company's product manager George Wat-son said that not only must panels carry CEmarking and the EN300 mark to prove theyhave been tested in accordance with structuralrequirements, they must also have certifica-tion to support their environmental claims

SmartPly is a leading manufacturer of orien-tated strand board (OSB) and Watson saidthe company has laid its own sustainabilitycredentials bare. OSB3 is a structural board thatcan be used in walls, floors, roofs and any ap-plication where the building regulations demandfully tested loading capabilities.

SmartPly OSB3 panels are fully certified by the

Forest Stewardship Council (FSC), becausethe wood used to manufacture them is legallysourced from Coillte Panel Products’ own forestsin Ireland. Watson said that this process is"underpinned by rigorous due diligence thatprovides a paper trail, documenting the wood’sjourney from forest to factory floor and on tothe timber or builders’ merchant branch".

Watson suggests this is what specifiers andtradesmen should fall back on: “If in doubt thebest advice is to check with the person youare ordering your panels from. They need tobe able to produce the paperwork to supportboth the structural soundness of the panels,as well as the certification and chain of cus-tody. The forthcoming EU Timber Regulationwill carry serious penalties for anyone sellingor purchasing timber that has been importedfrom outside the EU without the correct doc-

umentation in place, so opting for SmartPlyOSB3, over for example a tropical plywoodfor structural panel applications makes goodlegal sense too.”

For some people OSB still carries stigma re-garding formaldehyde emissions. Watson’s ad-vice on this again is to seek out products thathave documentation to support their claims:“All organic material contains some level offormaldehyde, because it is a naturally oc-curring chemical. However, with concern over thelevels of formaldehyde in some wood panelproducts which use it in their resins, it’s goodto know there’s an alternative.”

SmartPly OSB3 is manufactured using "ad-vanced resin technology" that results in ahigh performance, zero added formaldehydepanel, Watson said.

Choose sustainable timber panel products, says SmartPly


News

Passive house can be affordable— Scandinavian HomesBuilding a passive house don't have to beprohibitively expensive, according to Lars Pet-tersson of veteran Irish passive house buildersScandinavian Homes.

He says that simple passive house designshelp to keep costs down.

He said that when architects design passivehouses with complex shapes, it just adds tothe cost. "We strive to make it simple," he said.

Pettersson also said that in his experience,some county development plans are quite hos-tile towards energy efficient house types. "Theplanning people do not seem to know or careabout energy performance and cost of build,"he said.

As an example, he said some local authoritiesmake passive homes more expensive withplanning stipulations that limit the depth of thehouse, making it necessary to build a narrow,longer house with greater surface area.

"You're nearly doubling the surface envelope,"

he said. "It's a terrible waste of resources to haveto build so much more surface area."

He said another example is the restriction onprotective overhangs of the roof in some localauthority areas.

"In passive houses this means overheating inthe summer unless the amount and size ofthe windows are kept down. It also meansgreater exposure to sun, rain and wind for thetop part of the walls and windows," he said.

He said that passive houses do have a higher cap-ital cost, but that it doesn't need to be prohibitive.

"[Passive house] is more expensive of coursebecause if you use twice as much insulationit costs twice as much, but it doesn't have tobe so much more expensive overall," he said.

Pettersson discussed planning issues furtherin the latest edition of the Scandinavian Homesnewsletter, which is available at scanhome.ie.

"No wonder that people are totally confused

when the [planning] guidelines published bythe authorities themselves seem so contra-dictory. Most of the recommended designsare very poor from a cost performance andenergy performance point of view. We find itdifficult to understand how some of these de-signs complement or fit in to the rural landscapeof Ireland," he wrote.

(above) A Scandinavian Homes passive house underconstruction, designed to meet less than 5 W/m2

peak heating demand

Dimplex Renewables has developed an air towater heat pump solution that the company saysexceeds the requirement of the new part L ofthe building regulations. Dimplex commercialmanager Jonathan Jennings described it as a"single technology solution that can deliver inall weather conditions".

"The new part L is difficult to meet not in termsof renewable energy contribution, but in termsof the 60% improvement required over the2005 standard on energy and carbon per-formance," he said.

According to Jennings, attempts to complythat include oil boilers may be untenably com-plex and costly. "In order to meet the new tar-gets [for a house with oil heating] a very highlevel of insulation and airtightness is required

with multiple technologies being employed,”he said, “including at a minimum a large andmaybe oversized solar system, wood burningstove, boiler and heat recovery ventilation.”He warned that even implementing such abroad range of measures may not guaranteesuccess in meeting the energy and carbontargets. "Excessive insulation levels and threeheat sources leads to a much higher buildcost, just to meet compliance," he said.

According to Jennings, Dimplex has developeda "unique" heat pump solution that can help toreduce costs for complying with the new part L.“With sensible and economic levels of insula-tion, without a full heat recovery ventilationsystem, it offers single heat source for all yourheating," he said, adding that a key advantage ofthe solution is that no back-up boiler is required for

extreme weather conditions, even for larger houses.

He added that the Dimplex heat pump solu-tion maintains its output right down to minus15C. The Dimplex LA MI range of air to waterheat pumps comes in four sizes ranging from6 to 16 kW, with SEAI Harp database registeredefficiencies of up to 386%.

"As recently shown on the SEAI fuel price com-parison, heat pumps deliver the lowest aver-age cost for both hot water and space heatingcompared to any other technology," he said,adding that the company can deliver bespokesolutions tailored to individual requirements.

(below) Dimplex Renewables are proposing their LAMI range of air to water heat pumps as a key part Lcompliance solution

Dimplex develops "new cost-effective part L solution"

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Saint-Gobain Weber external insulation upgrades LeicesterVictorian solid wall properties in selected areasof Leicester are being treated to a whole houseupgrade to improve thermal performance. Anexternal wall insulation (EWI) system bySaint-Gobain Weber has been applied to therear of the dwellings and finished with a brick-effect render to match neighbouring properties.

This project upgraded hard-to-treat propertiesthat open directly onto paved streets. Localplanning restrictions overruled any measuresthat could impinge on the already narrowfrontage. This required a hybrid approach toinsulation with EWI applied to the rear andSaint-Gobain Celotex PIR insulation appliedto the interior walls of rooms at the front of theterraces. Other measures included insulationto lofts and floors, boiler and radiator upgradesor replacement, the introduction of smart gas firesto replace old electric wall heaters, and draftproofing throughout the two-storey terraced homes.

The projected was managed by the Asra hous-ing group, and the pilot scheme covered 175properties in three areas of Leicester.

The Weber.rend RB render is designed to pro-duce an "authentic brickwork pattern" using acombination of two polymer modified mortars.The brick pattern is achieved by cutting throughthe Weber.rend RB face coat to expose thecontrasting base render.

The Weber.therm XM EWI system uses 90mm

thick grey expanded polystyrene (EPS).

In these homes the target U-value using theWeber.therm XM EWI system with 90mm ofencapsulated polystyrene insulation boardwas 0.30 W/m2K – a modest improvement bypassive house standards, but significantly betterthan the original which in some cases was inexcess of 2.1 W/m2K.

“This house was freezing and we often had

the heating on all day but now we keep turn-ing it down the warmer it gets," said residentYasmin Sida, whose house underwent one ofthe upgrades. "And the new ‘brickwork’ hasmade it look brand new. We are very pleasedand we know our heating bills will be muchlower which is very good."

(above) A composite photo reveals how the brick-work pattern compares to the original brickwork onan Asra Housing property in Leicester

Insulation and airtightness expert Isocell hasadvised anyone involved in building projectsto consider custom airtightness tapes.

"Isocell’s comprehensive range of custom andstandard products eliminate the need for makeshift,less suitable products," said Isocell Ireland'sStuart Prause.

The company offers a large professional se-lection of membranes, tapes, grommets, EDPMrubber seals, butyl and alu tapes, sealants,compressed joint tapes, specialised high gradediffusion open foam, as well as primers andadhesives for achieving air and windtightnessin new build or renovation projects regardlessof the build make-up.

"The combination of the Isocell Omega wind tightsystem, cellulose fibre insulation, and IsocellAirstop system ensures a perfect solution thatworks in harmony," Prause said.

He added that the company's window systemhas been a favourite in school projects acrossIreland, helping specialised certified Airstop

system installers such as Airstop.ie achievewhat Prause said were the "best results in air-tightness in any school during 2012". Headded that the Isowindow system is particu-larly suitable for masonry buildings.

Prause said that the Isowindow system iscustomisable in width, which means that aswell as meeting traditional depths, it can caterfor the deeper reveals commonly found in lowenergy and passive structures. "Isocell is thefirst company in Ireland to offer custom widthtapes of this nature as required on demandto the Irish and UK markets," Prause said.

Isocell have over 23 years’ experience inmanufacturing and developing airtight prod-ucts. Prause said that Isocell is a Europeanleader in its field and number one in manycountries, including Austria, where the com-pany was founded. Isocell's projects in Irelandhave included certified passive houses, plusNorthern Ireland's first "carbon neutral" home.The company also supplied the new £50 millionGlasgow School of Art building with spe-cialised membranes sealants and adhesives.

Prause said that Isocell is the chosen airtightsolution provider to some of the largest con-struction and window companies in Irelandand the UK including Munster Joinery, Dug-gans Window Systems, Eco Timber FrameCork and Stewart Milne Timber Systems, theUK's largest timber frame provider. The com-pany also offers support, training and back-up.

(above) An illustration of Isocell’s Isowindow tapes,which come in customisable widths

Consider custom airtightnesstapes for low energy buildings— Isocell

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Ecological Building Systems launch structuralairtight boardEcological Buildings Systems are now sup-plying Durélis VapourBlock, a chipboard productthat provides vapour control, structural require-ments and airtightness.

Many building projects have used taped andsealed 18mm OSB3 as an airtightness layerto reach passive house and other low energybuilding standards.

However, Ecological Building Systems saidthat on-site experience, coupled with a studyby the Building Physics Laboratory at the Uni-versity of Leuven, demonstrated that OSBpanels on their own may not always achieveuniform airtightness.

“When dealing with passive house levels ofairtightness, there is no room for compro-mise," said Niall Crosson, engineer with Eco-logical Building Systems. "Based on our ownexperience and feedback from contractors ona number of sites, some projects failed tomeet their airtightness requirements due tounforeseen air leakage through OSB, even18mm thick.

"Of course it is critical that the joints and pen-etrations in these boards are sealed to a highstandard, but if air leakage occurs directly thoughthe board this can add significant complicationsand costs to a project."

He added: "With Durélis VapourBlock speci-fiers and contractors can be assured the

boards will provide a consistent airtight layerto the highest industrial standards.”

Durélis VapourBlock is a 12mm, 2400 x 1200mmhigh density chipboard with a factory fittedtransparent airtightness and vapour controllayer, Topfinish, on one side. This surface ap-plied finish is designed to guarantee consistentairtightness and vapour control. VapourBlockis for internal use. It is classified as a gradeP5 structural board which is suitable for use

in humid conditions equivalent to OSB3.

It is suitable for use in service class 2 (re-strictions in temperature and ambient humidity)and can be used in biological hazard classes1 and 2 of EN 335-3. Durélis VapourBlock is alsosuitable for load-bearing applications in humidconditions (service class 2 to EN 1995-11).

(below) Durélis VapourBlock, now available through-out Ireland and the UK via Ecological Building Systems

Passive house founder Professor Wolfgang Feistwill receive a fellowship from the Royal Instituteof British Architects in London on 6 February.

During his trip to the UK he will also be visitingexemplar passive house sites in London andNorwich, organised by the Passivhaus Trust,and giving a talk on 5 February in the Uni-versity of East Anglia.

"I feel extremely honoured to have been se-lected for such a prestigious award fromsuch a highly regarded organisation as theRoyal Institute of British Architects," ProfFeist said. "The extent to which the passivehouse standard supports good architecturehas been demonstrated by RIBA’s recogni-tion of my work in the field. High levels of en-ergy efficiency and excellent architectural designgo hand in hand, with all building shapes andstyles possible."

He added: "This award also confirms that passivehouse has become established in the UK withmany passive house buildings already builtthroughout the country."

Passive house founder toget RIBA fellowship

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Usher Insulations is planning to run furtherpart L compliance seminars in 2013. Targetedat contractors, the seminars will offer guid-ance and advice on complying with part L ofthe building regulations. The company ranthe first seminar last year in conjunction withIsover, Kingspan and Michael Hanratty of IrishHome Energy Rating.

Michael Usher of Usher Insulations told PassiveHouse Plus that it is essential that contrac-tors become familiar with the requirements ofpart L, particularly as some start to thinkabout building showhouses to test the marketagain. He pointed to the shortage of three andfour bed semi-detached homes in Dublin and

the surrounding area. "There would be a possi-bility of sales in that area," he said.

"You have to make sure that when they go tosite, before they even turn a sod, they knowprecisely what they have to do to achievecompliance," he said. Usher Insulations providespart L consultancy for anyone unsure of howto achieve compliance with the regulations.

The first seminar was attended last year by25 contractors. "They left leaving more awareof what they had to do in order to comply," MichaelUsher said. While details of this year's semi-nars have yet to be announced, he said anyoneinterested should contact the company.

Usher plans part L compliance seminars


News

Internorm to present passive range at Ecobuild

Leading low energy window manufacturer In-ternorm has said it will present "one of thewidest ranges of passive house and low energywindows and doors available" at this year'sEcobuild show in London. The company will alsobe launching a range of new products at the event.

Internorm’s extensive offering includes uPVCand uPVC/aluminium windows in addition totimber/aluminium windows. The uPVC anduPVC/aluminium products have "excellent thermalperformance" with U-values down to 0.74W/m2K,the company said. Their timber/aluminium win-dows deliver U-values down to as low as 0.63 W/2K.

The timber/aluminium range also offers a choice

of spruce or larch interior finishes. Internormalso said the performance of their timber/alu-minium windows is "enhanced by an innova-tive composite construction that incorporatesa highly insulating thermal foam".

Internorm's windows also feature Solar+ glass, athermal coating available on all their triple-glazedwindows as standard. The company said thatSolar+ triple-glazing maximises the potentialenergy gains provided through solar irradiationand prevents subsequent heat loss through thewindow.

Internorm’s blind products include I-tec Shad-ing, a specialist self-powered solar blind. The

company has also recently launched its firstRIBA-approved CPD, which provides archi-tects with an "insight into building low energyand passive house standard properties in ad-dition to how windows and doors play a sig-nificant role" in such buildings.

“Windows and doors are a key component ofany building – they provide a function as wellas having an aesthetical purpose," Internorm'sThomas Hagen said. "Getting the specifica-tion correct is paramount for the long-termbenefits of the building. With our extensiveexperience, we are perfectly positioned in pro-viding architects, specifiers and end clients theright advice in selecting the correct product.”

Leading Cork-based residential contractorMagner Homes are on track for certificationas passive house consultants from the Pas-sive House Institute. Magner Homes havebeen building to low energy standards since2006, the company said, most notably build-ing the first certified A-rated house in Ireland.

The company's Ed Magner said this latest de-velopment seeks to formalise the company's"vast on-site experience and knowledge gar-nered from the past six years".

He said Magner Homes has been busy on theground developing low energy projects andthat they are now "taking the opportunity todemonstrate their competence by following aformal, globally recognised certification path".

“We are extremely fortunate to have the PassiveHouse Academy, a Passive House Institute

accredited training body, based in Ireland," hesaid.

O'Donoghue said that one of the most inter-esting aspects of the process has been thefocus on the 'business case' for building to thepassive house standard.

“As a company, we intuitively understand andbelieve in the benefit of building to the passivehouse standard,” he said. “However, given thetighter budgets that many clients are havingto work with it can be difficult to communicatethis message. As certified passive house con-sultants we will be able to calculate the fi-nancial benefit that pertains to each client’shouse design if they decide to take it to thepassive house standard. That’s what mostpeople are interested in."

O'Donoghue said that Magner Homes have

modified and developed several constructiondetails to ensure that their houses meet pas-sive and low energy building standards. Theserange from thermal bridge free EPS founda-tions to hybrid roof constructions.

Magner Homes now plan to push deeper withPassive House Institute certification through-out the company. "The recent introduction ofthe certified passive house tradesman quali-fication means that we’ll be able to demon-strate that we have the skills and knowledgeto deliver to passive house standards at alllevels of our organisation," he said.

“The passive house standard can be difficultto understand for clients. The certificationstandards of the Passive House Institute cangive them comfort that Magner Homes candeliver the performance that passive housepromises.”

Magner Homes invest in passive house certification


News

DIT student wins RIAI traveling scholarshipThe Royal Institute of the Architects of Irelandhas announced that DIT student Thomas Sandersis the winner of its 2012 travelling scholarshipaward. The event was sponsored by sustain-able flooring company Forbo.

The presentation, opening of the exhibition andofficial launch of the 2012/2013 brief took placeat the Darc Space, 26 North Great George'sStreet, Dublin 1.

The theme for the competition was 'Urban 2012'.The RIAI said that "many of the schemes metthe challenge of this theme head-on with well-considered proposals for building in a sensi-tive urban location". A total of 90 entries werereceived from four schools of architecture —Dublin Institute of Technology, University Col-lege Dublin and Waterford Institute of Tech-nology and University of Limerick.

The aim of the travelling scholarship is to pro-mote the study of contemporary architecture.The competition has been held in a number ofguises since 1935. From 1955 to 1970 the RIAIoffered a scholarship annually to enable thewinner to make a two-week study tour of Romeat Easter. From 1971 to 1980 it was awardedto the best portfolio of post-intermediate stu-dents nominated by UCD and DIT. Every yearsince 1981 a formal architectural competitionhas been held for fourth year students.

RIAI president Michelle Fagan said that thescholarship is an important opportunity for stu-dents to research and explore issues that willinform the future of architecture, and to buildconnections between students.

She said that fourth year marks the point wherea student’s attitude and approach as an ar-chitect becomes significant, marking the de-velopment of their reputation as an architect. Commended certificates were also presented

to Tommy Borthistle, Lisa Erinhof, Anna Reidy,Noel Roche and Ronan Power.

Forbo – who have been approved by greenbuilding association Éasca based on theirsustainability credentials – will continue assponsors for the 2012/2013 event.

Pictured (left to right) are Forbo Flooring’s DeclanCarolan, RIAI President Michelle Fagan, and RIAI Boardof Architectural Education chair Martin Donnelly

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PV Tech supply huge solar array to Cork broadcasterGalway-based renewable energy supplier PVTech recently completed one of the country'slargest solar photovoltaic installations. Thearray was installed at the new low-energypremises of outside broadcasting companyTVM at Bartlemy, Co Cork.

PV Tech's Mike O'Rourke said his company in-stalled a 32.5kW array of German-manufac-tured Hanwha Q-Cells Q.Pro polycrystallinepanels, along with three 3-phase 10kW Stecagrid tie inverters. The array is situated on theroof of the facility's new warehouse. The in-stallation consists of 130 panels covering ap-proximately 217 sq m of roof area.

O'Rourke said that PV made particular sensefor TVM because, together with the use ofmore energy efficient equipment, it limited theneed to upgrade the incoming electricity sup-ply for TVM's new, larger facility.

"Similarly, they wanted to reduce the runningcosts by producing a chunk of their own elec-tricity," he said. The array will produce around28,000 kWh of electricity per year, displacingapproximately 68,000 kWh of primary energyusage and providing an annual energy sav-ing of between €4,000 and €5,000, accordingto PV Tech.

The system also reduces CO2 emissions byapproximately 15,000kg per year, which willassist TVM in achieving some of the ambi-tious environmental targets set by some oftheir major clients, O'Rourke said.

He added that the building has been constructedto rigorous low energy standards and fea-tures highly energy efficient appliances andlighting systems and is designed to need min-imal heating and cooling.

The PV system, designed and supplied by PVTech, and installed by Elementary Energy, wasinstalled and commissioned in October 2012.

A web monitoring system will provide real timedata on the system's performance to keeptrack of how much electricity the array is pro-ducing, and enable the client to compare theirenergy production pattern to their energy usagepattern. This data will enable them to makeappropriate changes to maximise the use oftheir self-generated electricity.

PV Tech specialise in grid connected and off-gridsolar PV systems for leisure, residential, com-mercial and telecommunications applications.

(above & below) A 32.5 kW solar photovoltaic arrayadorns the premises of outside broadcasting com-pany TVM at Bartlemy, Co Cork

The Renovate Europe campaign has welcomedthe European Parliament's call for the rate andquality of building renovation to be substantiallyscaled up in order to reduce the energy consump-tion of Europe's existing building stock by 80% by2050 compared to 2010 levels. The call is con-tained in the parliament's report on the Euro-pean Commission's Energy Roadmap 2050.

“Energy efficiency is a cost-effective way forEurope to achieve its long-term energy-saving,climate change, economic and energy securitygoals,” the report says.

Renovate Europe said that the document recog-nises the huge energy savings potential and eco-nomic benefits which currently lie dormant in the

EU’s building stock, and that it reiterates the key rolewhich energy efficiency must play in the EU’s transi-tion to a competitive low carbon, low energy future.

Achieving the reduction in energy demand ofthe EU’s building stock by 80% by 2050 wasalready established as a cornerstone of theEU roadmap for moving towards a low-carboneconomy in 2050, which was agreed in 2011.

“Aligning all actors, in the public and privatesector, but also at consumer level, around thesame goals of reducing the energy demandof the EU’s existing building stock by 80% by2050 is a fundamental step to achieving theEU’s goal of a competitive low-carbon andlow-energy economy by 2050,” said Adrian

Joyce, campaign director of Renovate Europe.

“The Renovate Europe campaign recognisedthis logical step in 2011, and set this target asthe main vision of its campaign, with the aimof delivering jobs, growth and lower energybills for EU citizens," he said.

The parliament’s report also calls on themember states to fully implement the recentlyadopted Energy Efficiency Directive, and toadopt ambitious long-term building renova-tion strategies accordingly.

Renovate Europe is a campaign initiated byEuroAce, the European Alliance of Compa-nies for Energy Efficiency in Buildings.

Renovate Europe welcomes EU parliament'scall for ambitious renovation targets

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Are you designing, building or pricing a sustainable building?Whether it's an energy upgrade of a small house, or you're lookingto achieve high green standards with a new home, office or factory,Passive House Plus can help.

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Energy rating advertising law

makes the invisible visible

One of my strongest memorieson the issue of energy efficiencyis what was said by a Danishpolitician Anne Grete Holmsgaard.She gave a presentation at anOireachtas committee in 2005and made the simple observationthat the biggest problem withinvesting in energy efficiency isthat you can't see it. You canbuy a €20,000 fitted kitchen ina showroom, and you do it becauseyou can show it off to friends whenyou have them over for dinner.

The very definition of insulationon the other hand is that what-ever you spend can't be seen.That's why I think the new reg-ulations on the requirement toadvertise Building Energy Ratingsare critical. We're all obsessedwith our homes. Now there's achance we'll become more ob-sessed with energy efficiency,because wherever a house isadvertised for sale or rental,people are going to see its energystatus as clear as day.

I think it's disappointing in thatlight to see some estate agentsarguing that we should maintainthe weaker regulations that existin the UK. To my mind there's onlyone word for that notion – it's daft.

Eamon Ryan

LeaderThe Green Party

The government should becongratulated on bringing in thenew BER advertising requirement.

This is exactly what was envisagedunder the original Energy Perform-ance of Buildings Directive in2006. Yet some professionalsare telling government that Irelandis going too far and is ahead ofother countries.

Au contraire, I was in La Rochellelast Summer. I noted that theenergy rating information oneach property was displayed inthe window of estate agents –well ahead of this re-cast dead-line for implementation.

This requirement shouldn’t beconsidered surprising or in anyway onerous. After all, the con-cept of giving consumers en-ergy ratings and thereforeempowering them to adjusttheir purchasing decisions ac-cordingly was the main inten-tion of the original directive.

Consumers have much to gain fromthis long overdue measure, to helpthem work out to what extentthe property they’re consideringwill be at the mercy of soaringheating costs.

Indeed the new advertising re-quirement should go further. Whenthe Department of the Environmentand SEAI made a joint presen-tation on the new requirementat the Custom House last Sep-tember, it was envisaged that forsale and to let signage wouldinclude not only the alpha numericBER score and BER logo but alsothe BER number that’s uniqueto each property.

This would have meant thatprospective buyers or renters couldsearch for the BER on the SEAIwebsite on the spot using a smartphone, and instantly access theBER including the advisory report,floor area, heating fuel type andheating system efficiency.

They could then estimate theirlikely running costs and look atthe potential for making im-provements.

Unfortunately inclusion of the BERnumber in signage did not makeit into the final guidance, althoughit is required in many other formsof advertising.

Nothing kills confidence like un-certainty. Consumer confidencein the property market has takena heavy hit in recent years. It'sgood that we now have an inde-pendent property price register.

By giving consumers tangibleinformation about the runningcosts and living conditions ofproperties, this belated recastmay help to rebuild consumerconfidence and encouragepeople to buy or rent again.

It’s clearly a better state of affairsthan the prospective buyer ex-pressing disappointment in the

BER result at the last minutebefore a sale is signed.

Richard Godley

Acting chairmanBER Assessors Association

Architectural technicians – a

neglected source of regulatory

knowhow

I note that the Royal Institute ofArchitects of Ireland has written toits members to notify them of theimportance of Deap, the softwarethat's used to demonstratecompliance with Part L of Build-ing Regulations. Deap was firstreleased in 2006. It's telling thatthe institute feels the need to flagthe significance of this in itscorrespondence with its membersat this stage.

The institute say that roughly 5%of architects have a working fa-miliarity with Deap – a remarkablylow level given the role of architectsin certifying compliance withbuilding regulations, since thesoftware has been the Part Lcompliance tool since 2007. I'dwager that if you were to pollarchitectural technicians, a vastnumber would know their wayaround Deap.

Architects, engineers or buildingsurveyors are the three professionsthat will be able to certify com-pliance with building regulationsunder the proposed buildingcontrol amendment regulations.Part L shows architects en masseare completely unprepared forthat. It's unfortunate that the in-stitute didn't lobby harder on behalfof its technician members to beanother profession who couldcertify compliance.

Brian Rochford

Architectural technician & certifiedpassive house designer

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Passive house and standards such asbuilding regulations, the Code forSustainable Homes, and BREEAM (theBRE Environmental Assessment Method)were developed for different purposesand consequently have fundamentallydifferent aims.

In the UK standards like this weredesigned to meet ‘top down’ politicalaspirations – currently a broad range ofenvironmental issues, including water andwaste, but most significantly ‘zero-carbon’building targets.

Passive house was developed fromthe ‘bottom up’ by building physicistsseeking effective ways to design lowenergy buildings and ensure that theyperform as predicted, in response toevidence that they were not. Passivehouse has a simple aim – to use gooddesign to achieve optimum internalcomfort for the lowest possible energyconsumption.

It isn’t possible to say that passive houseis the equivalent of a certain code levelor vice versa. Whilst the heat loss ofpassive house meets the heat lossparameter requirement for level six – thehighest level in the Code for SustainableHomes – a house designed to meetany code level, even six, won't meet thepassive house energy standard. Giventhe code’s zero carbon targets, pas-sive house can’t achieve level five orsix without adding renewables.

Rather than trying to calibrate betweensuch different standards, it’s moreuseful to highlight discrepancies.

Zero-carbon buildings – a flawed

target?

I believe the core idea of the code andregulations, that buildings are perceivedas isolated ‘zero-carbon’ islands, isconceptually flawed.

Firstly, it’s based on ‘offsetting’ carbonemitted by continued energy consumption,rather than actually ‘cutting’ the emissionof carbon by reducing energy use.

Secondly, it requires renewables onbuildings despite the reality that theseare generally less efficient and lesseconomic than renewables at a com-munity, regional or national scale.

Thirdly, carbon targets encourage thedesign of less, rather than more efficientbuildings. The easy option of addingrenewables or changing the heat sourceenables poor design to achieve com-pliance, regardless of whether therenewables or specified heat sourceare actually used.

A more effective strategy to reduce na-tional carbon emissions would focus onimproving building design to reduce energyconsumption regardless of heat source, andseparately generating low carbon energy onthe most effective and efficient scale.

That is what passive house offers –a rigorous way of designing efficientbuildings that consume less energy.

Broad issues

To ascertain overall environmentalratings, BREEAM and the code giveuniversal weightings to very differentfactors. This can result in anomalies,and the addition of features in orderto score points that are inappropriatefor that particular building.

For example to achieve code level fiveor six most dwellings require rainhar-vesting or greywater recycling even whenthis increases carbon emissions or issustainably questionable. Cycle racks,nearby shops and considerate contrac-tors are important, but should theyoffset more energy efficient buildingdesign? Money can be spent on tickbox procedures, rather than actuallyimproving building performance.

Being based on achieving a percentagecarbon improvement compared to anotional base building, the UK Build-ing Regulations encourage inefficientdesign. With a poor base design youcan more easily achieve notional im-provement and compliance. By settingan energy target per square metre peryear for all buildings, passive houseeliminates this anomaly. Buildings thenhave to be designed to reduce energy.

Accurate prediction

Compared to passive house, Sap – theUK software to demonstrate Part Lcompliance and generate energy ratings– uses optimistic assumptions, includingover-generous incidental internal gainsand underestimated heat losses forthermal bridges. This results in inaccuratelylow predictions of required thermal energyand reduces the incentive to improvedesign, making it a poor design tool.

Passive house uses pessimistic andcautious assumptions, which makes com-pliance harder and incentivises designimprovements over and above other meas-ures. Developed through many yearsof real life monitoring, it allows for thefact the built reality will fall short of esti-mated theory, and achieves buildings thatperform as well or better than predicted,making it an effective design tool.

Conclusion

The broad box ticking environmental

aims and zero-carbon targets of UKstandards encourages contradictorysolutions and complex design. The rad-ically low energy target of passive house,and its rigorously accurate process,encourages simple solutions and in-tegrated design.

Because passive house aligns withArchitype’s long standing belief that thebasic architecture should, by design, doall the hard work in saving energy, wehave integrated passive house into ourstandard design approach.

In 2009, St Luke’s in Wolverhampton wasthe first primary school in Britain toachieve BREEAM Excellent. We’ve nowcompleted three certified passive houseschools and have a further school currentlyon site. We’ve just received planningapproval for the UK’s first passive housearchive building, have submitted theplanning application for a major newpassive house building for the Universityof East Anglia, and this month we’ll besubmitting the planning application fora scheme of 150 passive houses inHerefordshire, for which we’ve formed anew development company calledArchiHaus.

We’re committed to passive housebecause it offers greater long term finan-cial benefits to our clients, a more com-fortable internal environment for usersand, most importantly, more effective longterm energy and carbon reductions.

Our experience and belief is that passivehouse does offer a logical, robust andaffordable solution for all building types,given the requirement to reduce carbonemissions and in the context of thecurrent economic climate.

Instead of relying on expensive andadd-on technologies to offset carbon, itencourages buildings that simply saveenergy by design. We’ve been achievingthis at no extra cost in a variety ofdifferent projects, through integratedthinking and a relentless focus onsimplicity of design.

With budgets under increased pressure,particularly in the education sector, achiev-ing passive house at no extra cost isincreasingly hard to achieve. However,once whole life costs are consideredpassive house wins hands down, withcapital payback in as little as five years,and significant revenue savings for thelife of the building with future proof-ing against ever increasing energyprices. This would release far moremoney in the long term to spend onteaching, than squeezing standardsand fees in the short term.

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Why passive house should replace flawed zero carbon aims

While it’s important to assess all aspects of a building’s environmental impact, UK effortson sustainable building have tended towards box ticking – often at the expense of truesustainability, argues Jonathan Hines of award-winning architects Architype.

“Carbontargetsencouragethe designof less,rather thanmore efficientbuildings”

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The recent rapid growth of passivehouse in the UK and Ireland has beena game changer. The number ofbuildings is still small but we alreadyhave multiple examples of detachedhomes, terraces, blocks of flats, offices,community buildings and primaryschools. Most are performing embar-rassingly close to the predicted energyand comfort targets. This is a statisticalanomaly of a small sample but it’s stillimpressive given the consistently poorperformance of most earlier attemptsat energy efficient building. This isone of the reasons for getting excitedabout passive house – it seems to work.

However I expect this wave of ex-citement to pass. Anyone jumping onthe bandwagon soon realises that it

requires effort. The first project isparticularly challenging because thepassive house approach requires at-tention to detail and is very differentto what we are used to. There is anawful lot to learn. Mistakes will be made.

This typically leads to one of threeresponses. 1) don’t do it again, 2)cherry-pick the easy bits and call itsomething apparently non-committallike ‘passive house principles’ or 3)embrace it, learn from the experienceand find ways to make it easier nexttime. Some who have embraced thechallenge decide to only take onpassive house projects. These peoplerealise that passive house is a wholeapproach, not just another thing to

offer clients alongside zero carbon,LEED and BREEAM – they can’t un-learn what they now know.

Passive house principles and fruit

flavoured drink

One of the great things about passivehouse is that it’s defined. ‘Low energy’or ‘eco’ are worse than meaninglessterms. One person’s green exemplarmight be someone else’s nominationfor a Mark Brinkley Eco Bollocks Award.By contrast it isn’t difficult to checkthe claim that a building is a passivehouse. The Passivhaus Trust documentClaiming the Passivhaus Standard1

clarifies what it means to claim abuilding is a passive house. It is alreadyhaving an influence internationallyand the Passive House Institute hasasked to translate it into German. Ifyou are involved in passive housethen you need to read it. If you findfault then help us improve it.

Passive house is an open standardand the term is not registered. Butbecause it’s understood to meansomething specific, to describe abuilding as a passive house is to makea very unambiguous claim underconsumer law. If you buy red shoesonline and they arrive as blue youcan claim your money back. Whatyou’ve built may be better than passivehouse but if it doesn’t meet the qualityassured definition then you need tocall it something else.

But what does it mean when peoplesay that they couldn’t afford to achievepassive house but are following passivehouse principles? Surely following theprinciples should result in a passivehouse. To my mind an acceptable usemight be to describe a building as,say, ‘built following passive houseprinciples but achieving a PHPP-cal-culated annual heat demand of 21kWh/m2/yr with a blower door resultof 1.1 air changes’. It’s almost a passivehouse but for some reason we justmissed the mark and are beingtransparent about our claim. In mar-keting terms straight passive houseis a simpler story – and a simple termfor honest near misses would be use-ful. But passive house principles can’tbe used loosely to mean a passivehouse flavoured building.

I am reminded of this quote:

“I was working as a physicist. I read

that the construction industry had ex-perimented with adding insulation tonew buildings and that energy con-sumption had failed to reduce. Thisoffended me – it was counter to thebasic laws of physics. I knew that theymust be doing something wrong. SoI made it my mission to find out what,and to establish what was needed todo it right.” – Dr Wolfgang Feist,founder, the Passive House Institute

15 years ago I had experimented bybuilding our home using what I thoughtwere passive house principles. Thefoundations are thermal bridge free,airtightness was 1.3 (n50). Insulationis continuous 400mm in walls androof. Ventilation is passive to avoidthe electricity to run fans, and heat-ing is by a single woodstove with noradiators. I have seen arguments thatlesser buildings than this are betterthan passive house so surely we cansay we have followed passive houseprinciples or even gone beyond them?But no, the ‘passive house community’won’t let us join their exclusive club!

Now that I know PHPP well, I’mpleased that they won’t let us call ourhouse a passive house as I have toreport that our house’s heat demandweighs in at around 90 kWh/m2/yr,six times that of a passive house. Itgets worse: performing an expensiveretrofit with passive house windowsand heat recovery ventilation wouldonly get our heat demand to around50 kWh/m2/yr. If I wasn’t able to pointto other even worse eco-exemplarson a weekly basis I might be too em-barrassed to share such an apparentlyspectacular failure. Had we modelledthis building in PHPP it would havebeen immediately obvious that theproblem is the form. Any experiencedpassive house designer would knowit’s not ideal but only the most expe-rienced would guess how bad ourlovely house is in energy terms. Thisisn’t a passive house problem; it’s alaw of nature problem. Whilst mostvisitors experience our home as warmand comfortable, a passive housedweller would be less than impressed.

So if what you are designing, building orselling is not a passive house, then callit something else. Otherwise it causesconfusion, annoys the passive housecommunity and is probably illegal.

1http://bit.ly/RWni95

If it’s not a passive house,don’t call it a passive house

Unlike popular terms like eco, green & sustainable, passive house has a specific meaning & shouldn’t be usedincorrectly, argues Passivhaus Trust technical director Nick Grant.

“Passive houseprinciples can’t beused loosely tomean a passivehouse flavouredbuilding”

I believe that all good architecture should alsobe sustainable architecture and I hope thatmy selection of buildings illustrates this verypoint. The six dwellings I have chosen inspireme for several reasons: from the Inuit’s igloosas bare shelters with minimal impact to ad-vanced passive house buildings. They sharesome remarkable strategies such as relianceon body heat for internal heat-gains and goodairtightness and – in the case of the Just-Kpassive house – also the utilisation of the nat-ural stratification of air. Le Corbusier’s 1950’sMaisons Jaoul with Catalan vaults and roughbrick is not well known but well-loved by its

current inhabitants (two families with youngchildren, since you ask). Like the majority ofbuildings at the time, the Maisons Jaoul areuninsulated apart from double glazing, but usethe local site context and the European ma-terial vernacular of brick and oak beautifully.Pushing the local vernacular and local mate-rial opportunities further are Geoffrey Bawawith his tropical, bioclimatic modernism in Sri-Lanka and the sublime Tyin Tegnestue with theirarchitecture of necessity, built with and forlocal communities with limited resources.

I think my selection of these projects gives away

what inspires me most: buildings which quietlymitigate and adapt to climate change, which uselocal materials and skills intelligently while draw-ing from local knowledge, skills and techniques.I particularly get excited by those projects whichuse contextual parameters to generate theirdesign rather than see it as a straitjacket forcreativity, and all projects presented here doexactly that, though each in very different ways.But I also believe, just like the Inuit when con-structing igloos, that we have to gain a deeperknowledge and understanding of locally avail-able materials and construction sequencesand techniques for how we design and build.

International selection

what we can learn from igloosNothing drives innovation like adversity. Facing up to the prospect of scarce energy and other resources,we can take inspiration equally from the Inuit and the most avant-garde of passive house designers, asSofie Pelsmakers reveals in her choice of six uniquely inspiring buildings from around the world.

Igloos,

the North American Arctic

Igloos were temporary hunting shelters built bythe Inuit population in northern Alaska, Green-land and Canada, and are only sporadically used.Igloos are built from local and renewable ma-terials with just a knife for cutting and shapingand can be erected by two people in less thantwo hours for a night’s shelter to two days fora larger one, where several igloos of different sizesare connected to provide more space and greatercomfort. They are built from 20 cm thick snow-blocks, cut out with a knife from the snowy groundsurface. To do this, sufficient snow depth is needed,so blocks can be cut out of the surface andlifted out, leaving the igloo’s floor one snow-block below the external ‘ground’ level.

The first snow-block layer is put in a circle andits height cut down to a sloping spiral beforeplacing the next layer of snow-blocks, givingit inherent strength. The igloo can then be builtentirely from the snow found within its ‘circle’.Light can be allowed in when using ice-blocksinstead of opaque snow-blocks.

Airtightness is crucial and blocks are shapedwith a knife to create tight joints betweenthem. Once all the snow-blocks are in place,cracks are plugged with snow from the out-side. The effect of breathing inside creates anice layer and an airtight layer while alsostrengthening the structure. Natural stratifica-tion allows the warmer air from people’s bod-ies to move up into the main igloo space atthe top, which is used for sitting and sleeping,often made comfortable with animal skins. Avery small gap at the top is allowed to replaceCO2-laden air with fresh air from a small holeunder the lower level entry tunnel, which isclosed with a snow-block. Due to the air-pockets in snow, it acts as an insulator in aharsh environment. This combined with asmall, compact space and body heat in an oc-cupied igloo, creates relatively warm internaltemperatures of around 15C. Though muchbelow the thermal comfort that we have cometo expect from our dwellings at present, this is animpressive increase from external tempera-tures which are several degrees below zero.

Yet the lessons from igloo-building are rele-vant, but often ignored, in today’s constructionin cold climates: the importance of airtight-ness, wind protection, dwelling occupancyand harnessing of internal heat gains. Toooften have we allowed the outside in when itis not desirable and we still are bad at pro-viding protected lobbies or wind-shelter.Igloos also teach us lessons about the use oflocal materials, construction techniques andknowledge, unrivalled by most architects or builders.Architects are generally removed from theconstruction process, while builders seem tobuild each house as a one-off prototype, not ableto take forward knowledge and skills gained. �

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(clockwise from opposite) Inuk hunter, Avataq, in polar bear trousers, lights stove inside an igloo in northwest Greenland; Qaaviganguaq Qissuk, an old hunter Inukuses a snow knife to build an igloo in northwest Greenland; a diagram showing how the sleeping area is raised above the entrance so that it retains any heat as hot air rises;an Inuk inside an igloo, circa 1900 – 1923; a community of igloos (Illustration from Charles Francis Hall's Arctic Researches and Life Among the Esquimaux, 1865)

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Just K,

Tübingen

Just K was designed by Amunt Architects inGermany for a family of six people. Just Iikethe igloo, the living spaces are at the top, andnatural stratification ensures that these arethe warmest spaces in winter. As in igloos,good airtightness is crucial to reduce heat-loss through cracks and the passive housestandard has been adhered to.

Its sculptural form was generated from its con-textual and constricted site conditions, suchas needing to allow original views from neigh-bouring dwellings to the vista’s beyond. An ef-ficient building fabric was achieved partly by

prefabrication and high levels of insulation, aswell as solar gain to harness the free heat andlight from the sun, while the sculptural form leadsto a vertically connected open space within alimited volume. The house can be split into twoapartments and is built almost entirely from locallysourced timber and prefabricated in a localfactory with a total of 136 pieces site-assembled.

The structural engineered timber has beenleft bare internally, providing a warm and ar-chitecturally interesting interior, while addingsignificant thermal mass to the fabric. The useof timber and vertically connecting spaceswith strategically placed openings, creates afluid interior. Its spaces resemble somethingvery different from what we have come tothink of as highly efficient dwellings and ishence inspirational in breaking this mould. �

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Haren 02,

Brussels

A re-interpretation of the efficient ‘box’ is alsowhat A2M Architects did in Haren 02, whichis a residential scheme of 30 passive housedwellings in the north east of Brussels, wherefrom 2015 all new buildings will need to meetthe passive house standard. The architectstook great care to design its urban form andgenerated ‘urban breaks’ – a vertical steppingof buildings to break regularity and allow for aless imposing street front. They also allow forsolar gain and views to internal and externalspaces beyond, while creating accessible roofterraces for residents. Rather inspirationally,the architects consciously decided a few

years ago to only accept passive house com-missions as they believe this is simply com-mon sense. They also undertake all of the buildingphysics and technical modelling themselves ratherthan outsourcing it, thereby creating a local hubof knowledge in their day-to-day practice.

Haren 02 is currently on site, and is likely tobe a game-changer for passive house in Eu-rope and elsewhere for several reasons.Firstly, the project is projected to cost around15% less than standard housing construction,achieved by prefabrication and as much off-site construction as possible to avoid wet tradesand speed up construction to around sevenmonths. Secondly, Haren 02’s projected pri-mary energy use is just 45 kWh/m2 per year –due to its passive house specification and someon-site renewable energy delivery. Once com-

pleted, the performance will be monitored. Inaddition, some of the dwellings are ‘zero en-ergy’ prototypes, illustrating that energy effi-cient buildings require less energy. Indeed, it ismuch easier for the remaining energy require-ments to be met with renewable technology,whether on or off-site, in efficient buildings.

Finally, Haren 02’s airtightness strategy is po-tentially more robust and longer-lasting: it re-lies on the use of prefabricated concretepanels without the need for airtightness mem-branes or tapes (joints will be siliconed in-stead, however the longer term performanceof this approach is unconfirmed). Such think-ing may spur the construction industry to gofurther still in working with the inherent quali-ties of materials to achieve airtightness morenaturally, so watch this space. �

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Maisons Jaoul,

Paris

In principle, I normally only write about build-ings that I have visited: there is no substitutefor spending time in a building to experienceand judge its qualities such as its scale, vol-ume, fluidity and changing light conditions andto gain a sense of how the building is usedand has weathered. However, the only buildingsincluded here which I have visited are the MaisonsJaoul by Le Corbusier, in the outskirts of Paris.

The two Jaoul family houses are far removedfrom Le Corbusier’s earlier and well known de-signs such as Villa Savoye or Maison La Roche.The Jaoul houses were designed in the early1950’s, in Le Corbusier’s more mature years,and it shows: the use of primitive techniquescombined with modern technologies such asthin Catalan vaults on thin load-bearing andrough brick walls with exposed rough con-crete, bright colours and plenty use of timberand sod roofs. In fact, there are no externalsuper-smooth white finishes in sight at all.

The vaults act as central hearths and refer toprimitive human habitations and shelters andwere regularly used by Le Corbusier in hislater dwelling designs. The placement of the twohouses on the constrained and overshad-owed site were generated by Le Corbusier’s

search for the greatest amount of exposureto sunlight and daylight penetration. Typically,the windows sit in window sections (‘pans deverre’), with glazed sections for day-and sun-light and opaque timber sections to provideventilation openings and built-in furniture. In-ternal timber wall panels also act as ‘aera-teurs’ to provide fresh air, located betweenspaces to allow for cross ventilation, while re-taining privacy. Moving timber shutters keepthe heat in on cold winter nights and make thehouse light or dark and all stages in between.One of the houses has beautiful rainwaterspouts and some innovative L-shaped win-dows were developed in response to strict by-laws. A tile is cast in the original tiled floors withinstructions to occupants for how to maintain it, afront-runner to occupant user-manuals, if you like.

Unfortunately the early double glazing failedand the current occupants say it is difficult tokeep warm in a cold winter as it was built be-fore insulation, thermal bridging or high ther-mal comfort standards mattered. Yet theMaisons Jaoul signify an important shift fromLe Corbusier’s much earlier work and are adeparture from the generic, standardised in-ternational modernism to a more regional andcontextual approach that most do not re-member the iconic architect by. This matura-tion was inspired by his interest in the localvernacular but also by learning and respond-ing to building feedback and mistakes, some-thing all designers should be doing.

(above and below) the combination of traditional andmodern evident in the Catalan vaulted ceilings, thinload-bearing walls and sculptural stairs; (top) the unin-sulated walls and primitive double glazing make thebuilding difficult to keep warm

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Ena Da Silva house,

Colombo

Geoffrey Bawa was influenced by interna-tional modernism and Le Corbusier’s earlywork and in the late 1950’s designed tropical‘modernist’ buildings in Sri Lanka, though lit-tle known outside South-East Asia. While white,reflective surfaces suited a hot, humid cli-mate, Bawa soon realised that pitched roofswith large overhangs rather than flat roofswere better to deal with torrential downpours,keep the sun out and to encourage naturalventilation.

From his interest in Sri Lanka’s architecturalheritage and building traditions, Bawa developedtropical courtyard designs with open spacesaround them to aid natural airflow and the EnaDa Silva House, built in 1960, is an example ofthis. It signifies Bawa’s deeper understandingof local climatic conditions and material useand blends modernity and tradition. Pitchedroofs are tiled with traditional materials whiletimber trellises provide screened views acrossthe courtyard. Inside and outside spaces areblurred, giving the feeling of infinite space andproviding a good cross flow of air. Bawa beau-tifully builds on the local vernacular, utilising prin-ciples of cross flow of air, courtyards and shading,to provide modern, bioclimatic architecturewith spaces that work and are inspirational. �

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Soe Ker Tie House,

Tak Province

Norwegian architects Tyin Tegnestue follow inthe tradition of the likes of Rural Studio, virtu-ously working for and with local communities,including utilising community skills during de-sign and construction. Among their many in-spirational projects I chose Soe Ker Tie House(Butterfly House) which was built in just sixmonths and for just $11,500 USD. They ex-changed skills, techniques and knowledgewith the local community, with whom they de-signed and built six dormitory houses for Burmeseorphanage refugee children on the Thai-Burmese border. Unlike most designers, TyinTegnestue were also involved in the construc-tion process, providing a critical learning andfeedback loop.

The six butterfly houses are built in timberwith a raised floor, using traditional bambooweaving techniques and locally sourced bam-boo for the facades. The butterfly shaped,lightweight tin roofs allow water to be col-lected in the rainy season for use in the dry sea-son. Bamboo is also utilised as ‘honeycombwindows’, giving security, privacy and light but

also natural ventilation and solar shading. Athigher level, openings with timber shutters areprovided for further air breezes while provid-ing solar shading. The result is playful, beau-tiful and sustainable and the product of sharingof knowledge, skills and creative forces with thelocal community. This is inherent of most of TyinTegnestue’s work: they tend to work in areasof need, with the local community directly involvedin the design and building, and they establisha mutual learning process. Due to the natureof projects and constraints of budget and re-moteness, local materials and skills are utilisedfrom project conception to completion. Ratherthan as acting as a constraint, this has helpedgenerate a new, local vernacular architecturewhich is truly delightful. Like the Inuit igloos, localmaterials have to be used within limited budg-ets and time constraints. Yet the architecturalresults are refined and poetic, despite (or thanksto?) it being an architecture of necessity.

Of course the beauty of their work is in part dueto the rethinking of traditional and local mate-rials and the local vernacular, which demandsin a hot, humid, tropical environment for air toflow freely in buildings and between spacesto provide thermal comfort. They reinventedlocally available materials and techniques todo exactly that, to a stunning effect.

ABOUT THE AUTHOR

Sofie Pelsmakers is a chartered archi-tect and environmental designer withmore than a decade of hands-on expe-rience designing, building and teachingsustainable architecture. She taughtsustainability and environmental de-sign and led a masters programme insustainable design at the University ofEast London. She is currently a doctoralresearcher in building energy demandreduction at the UCL Energy Instituteand co-founder of Architecture for Change,a not-for-profit environmental buildingorganisation.

She is author of The EnvironmentalDesign Pocketbook (RIBA Publishing,2012), which synthesises her practicaland academic expertise to support thebuilding industry towards a significantchange in its design and building prac-tices. It received commendation for theRIBA’s 2012 Presidents Awards for Out-standing Practice Based Research.

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A new house in Wexford is the firstin the country to achieve an A1Building Energy Rating and certi-fied passive house status – ar-guably making it the most energyefficient building yet built in Ireland.So why did a regulatory flaw riskrendering it non-compliant?

Words: John Hearne & Jeff Colley

Francis and Brigid Clauson’s new self-build isarguably the most energy efficient house yetbuilt in Ireland. Yet it almost failed to meet buildingregulations. When working through the calcu-lations for his Building Energy Rating (BER)Clauson discovered that though his plan wouldcomfortably meet the highly onerous passive

house targets, it would actually breach the re-newable energy obligation under Part L of thebuilding regulations.

Long before he broke ground on his elevatedsite in Bunclody, Co Wexford, Clauson carriedout an enormous amount of research. In ad-dition to many hours on the internet, he talkedto dozens of professionals and went to visithouses and sites to question people about thechoices that they had made. “I’m absolutely ma-niacal on detail,” he admits. “I questioned everysingle individual extensively about what theywere telling to fully validate their responses.”

An IT professional by trade, Clauson and thedesign team he chose used two software pack-ages to design and model the energy per-formance of the building. Deap – the DwellingEnergy Assessment Procedure – is the Irishequivalent of the UK’s Sap software, and isused to calculate Building Energy Ratings anddemonstrate compliance with energy efficiency

targets under Irish building regulations. PHPPis the software developed by the PassiveHouse Institute for the design of passive houses.In order to fully understand both, Clauson ac-tually built a model which married them to-gether. It was while working through thefigures on his hybrid model that he turned upthis startling anomaly: his house was so en-ergy efficient he couldn’t generate enough re-newable energy to meet minimum requirementsset by the Department of the Environment.The house just didn’t have the energy de-mand. “If you need 50 to 75 kWh/m2/yr – asan A3 house would – then it’s easy to gener-ate 10Kwh/m2/yr of renewable energy,” hesaid. “But as you reduce this demand to say30 kWh/m2/yr the percentage of overall energywhich has to come from renewables grows –and thus becomes harder to achieve.”

The problem stems from the changes to PartL of the Irish building regulations introducedin 2007, when renewable energy systems be-

IRELAND’Smost energy efficient

came mandatory for all new homes, along withunprecedented improvements in terms of bothenergy efficiency and carbon emissions. Theregulation itself doesn’t go into detail. Insteadit makes some general statements about en-ergy efficiency, carbon emissions and renew-able energy. It states that new homes mustbe designed and built “to limit the calculatedprimary energy consumption and related car-bon dioxide emissions insofar as is reasonablypracticable”. It then adds the requirementsthat a “reasonable proportion” of that energydemand must come from renewable sources.There’s a subtle but important point in thiscumbersome language. The regulation saysthat energy demand and carbon emissionsmust be reduced to the greatest extent possi-ble without going to unreasonable lengths, but itdoesn’t go so far with renewables – it only re-quires that renewable energy makes up a rea-sonable fraction of the total energy demand.

These general statements are fleshed out into

clear targets in the technical guidance documents(TGDs). When the new Part L was published in2007, TGD L was also updated. It defined the en-ergy and carbon saving targets as 40% reduc-tions in primary energy for space heating, hotwater, cooling and lighting, rising to 60% reduc-tions in changes to TGD L from December 2011.But both changes to TGD L set the renewablestarget at a fixed number – 10 kWh/m2/yr of thermalrenewable energy, or 4 kWh/m2/yr of microgen-erated electricity. This wasn’t a widespread prob-lem for people building to scrape compliancewith TGD L 2007, as for most building types the40% energy reduction target still left a reasonablechunk of primary energy, meaning renew-ables still had a demand to help meet. For somesmaller house types a fairly small solar thermalarray could hit the 10 kWh/m2/yr target. Biomassboilers could typically comply, as could manyheat pumps in spite of being penalized for vari-ous reasons outlined below.

According to the Department of the Environ-

ment, meeting the targets set out in TGD L in-dicates “prima facie” evidence of compliance– a legal term which means that building tothe levels set out in the TGD ensures compli-ance with the regulation. The department is onrecord as saying that the only way to actuallyguarantee compliance is to hit the targets statedin the TGD. When pressed on this point byPassive House Plus editor Jeff Colley at theSee the Light conference in Dublin in Septemberlast year, a department spokesman said thatpeople who’ve built very low energy homesand therefore failed to meet the renewablestarget would need to take their cases to courtif they’re to prove compliance.

Clauson had determined that the most pragmaticway of heating his super low energy housewas by using a heat pump. The problem how-ever is that the house is so well insulated, soairtight and so cold-bridge free that very littleheat is actually needed. Clauson’s solution wasto choose a heat pump capable of being �

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programmed to match the building’s actual heatloss on a live basis: a Danfoss air to water heatpump installed by Heat Doc Ltd. “For super lowenergy houses that ability to auto adapt andadjust minute by minute is key to maintainingcomfort levels,” says Mike Teahan of Danfossdistributors Heat Pumps Ireland. “Most modernheat pumps have this built in functionality.”

But both Deap and the new regulations giveheat pumps a hard time. TGD L stipulates thatonly energy above a seasonal performance fac-tor (SPF) of 2.5 can be counted towards the 10kWh target to take account of the primary energyof grid electricity due to generation and trans-mission losses. According to Deap, every kilowattused by the heat pump takes 2.42 kilowatts ofenergy use at the power station – 10% lowerthan the 2.7 kilowatts Deap listed till 2011.

Energy from the heat pump to provide hot watercan be counted towards the 10 kWh target, thoughthis portion of the heat pump’s output is sub-ject to a 25% penalty to take account of effi-ciency losses at higher temperatures.

But other penalties are due to the software’sdifficulties handling non-traditional heating ap-proaches. Deap assumes intermittent heating– where the building first goes cold and isthen quickly loaded with high temperature heat.“The problem is that Deap is treating your heatpump as if it’s a boiler,” Mike Teahan explains,adding that the problem would have been ex-acerbated if Clauson had paired the heat pumpwith radiators. “When you plug a heat pumprunning on rads into Deap it automatically as-sumes you have an on/off cycle of heating up

and cooling down. If you heat a building in thisway you’ll have to use the heat pump at high

temperature to bring the building back to thedesired temperature quickly. But if you use a �

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(above left) airtightness detailing was a painstaking, iterative process to make sure it was done right; (aboveright) the house was built using standard blocks, with a 250mm cavity which was pump-filled with bondedbead cavity insulation; (below) client Francis Clauson on-site during the build

(p43, clockwise from top left) a room sealed wood burning stove can supply heat in the living room if re-quired; (right) thermal bridges at foundation were dealt with by using Quinn Lite blocks in the rising walls;an airtight and thermal bridge free wide cavity window sill detail

“The construction detailsand solutions are familiarto a lot of Irish tradesmen.”

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heat pump with rads, full weather compensa-tion, and minute-by-minute control, you don’thave to have the rads at high temperatures. Thetemperature of the rads changes subtly as theweather changes.”

Teahan has a word of caution regarding howmany people think the renewables obligationworks. “Most people seem to think that if youwork out the size of the house times 10 kWh, that’swhat you need to provide from renewables.That’s not the case at all. What you’re actuallyrequired to do is bring the BER result of thehouse down by 10 kWh/m2/yr.”

Clauson worked out in Deap that his heatpump would provide just 5.21 kWh/m2/yr to-wards the renewables obligation whereas his

total energy demand is 42.64 kWh/m2/yr, so theproportion of energy provided by renewabletechnologies needed to be 23%. The big ques-tion is, does this 23% represent a ‘reasonableproportion’? What if Francis Clauson decidesthat it does but the building control officer de-cides that it doesn’t?

Once he’d discovered this flaw, he went on toconduct a series of experiments on Deap. Hereduced his thermal bridging values back todefault figures, thereby seriously compromis-ing the integrity of the building envelope. Theexercise pushed the heat pump’s contributionto the energy needs of the house up to 9.3kWh/m2/yr. Still not enough. Then he reducedthe air tightness from the passive standard tar-get of 0.6 air changes per hour to the default7 m3/hr/m2, and this finally pushed his renew-ables contribution above the TGD L threshold,to 15 kWh/m2/yr.

Though these changes moved the renewablescontribution from 5.21Kwh/m2yr to 15 Kwh/m2/yr,they made the building less energy efficient.“This is barmy,” says Clauson.

The other alternative – and the one Clausonchose – was to add additional renewabletechnologies to his house, in this case a solarphotovoltaic array. “If I threw away my windowcertificate and threw away my heat recoverycertificate and just reverted to default values,I wouldn’t have needed to put the PV panelson the roof,” he says. “You could say that myPV is eco-bling but I had to put it in place tocomply with the regulations. But that said, atChristmas it enabled me to cook my turkeyand ham for nothing!”

Ironically, Clauson’s original intention hadn’tinvolved passive house, or even low energy.“The whole point of the house was really tocapture the sun throughout the day, but as wegot further through the process, we realisedthat the difference between part L of the 2011regs and passive is insignificant. That’s when

we decided to go for it.”

He engaged architect Zeno Winkens andArchie O’Donnell of Integrated Energy as en-ergy consultant, and got a local contractor, ChrisGahan of GR8 Construction to do the work.

Zeno Winkens says that at the outset, Clau-son provided him with a sketch together witha highly detailed brief – “nearly down to thehooks on the back of the door in the children’sbedroom�” Taking this brief as a wish list,Winkens carefully assessed the site andcame up with a design that married the client’sneeds with passive principles. “The site wasn’t100% north south, it was coming in at an angle,that’s why I chose the L design with a cut-off cor-ner,” he says. “Though it’s quite a large house,from the road, it still manages to look quitemodest.”

With design, orientation and layout agreed,the design team moved on to how the housemight be built. “I followed the mantra of the fourPs,” Clauson explains. “Passive, pragmatic,price-conscious and practical. Any measurewe took had to hone into those four.”

He investigated both timber frame and exter-nally insulated options but elected in the endto go with a conventional building method – astandard block built wall, albeit with a wide,250mm cavity. The robustness of the blockwas a big attraction for Clauson, plus the wayit dealt with the Irish climate on what would bea very exposed site. The fact that it is such along established construction method andthat there was extensive local expertise wasalso a deciding factor. “What’s critical aboutthis project is that it’s been built by local tradeusing local materials,” says Archie O’Donnellof Integrated Energy. “When we started doingpassive house a lot of the techniques andtechnologies would have been copied fromcentral Europe and I think what’s useful aboutthis is that the construction details and the so-lutions are ones that are familiar to a lot of �

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Irish tradesmen.”

Chris Gahan of GR8 Construction says thatthe exhaustive research and huge level ofpreplanning that Clauson put into the projectwas central to it success. “Francis had weeklyor fortnightly meetings, complete with agendas,so it was run more like a commercial job thana one-off house,” he says. “To get to passive,you have to be detail oriented, we all knewthat starting out. To be honest it ran very well.”

Thermal bridging issues at foundation levelwere dealt with through the use of Quinn Liteblocks in the rising walls. Thereafter, design-ing away cold bridges and ensuring airtight-ness with a wide cavity construction involvedthe drafting of more than twenty individual de-tails in a painstaking, iterative process. “Eachdetail was investigated by the design team,”says O’Donnell. “They would have been im-proved, they would have been put throughthermal analysis, further improvements wouldbe made, then we’d coordinate with say aplumber or an electrician and improve thosedetails yet again.”

Installing the windows did present particularproblems. Alan Tier of Integrated Energy ex-plains that their initial aim – for aesthetic andbudgetary reasons – was to install non-ther-mally broken ‘lift and slide’ windows as op-posed to passive certified, thermally broken‘tilt and slide’ windows. It is, he explains, the-oretically possible to install non-passive stan-dard windows and still achieve a passive standardperformance, so long as no point of the inter-nal screen is allowed to fall below 13 degrees.Tier modeled the windows exhaustively withthis aim in mind, but in the end, he had to concedethat due to the surface area of the building, itjust wasn’t possible. Instead, a combinationof both passive and non passive certified win-dows were installed.

“Probably the biggest challenge was gettingthe airtightness membrane around the re-veals and getting that to interface with the in-ternal leaf of block work,” says Chris Gahan.

Aided by the day lighting benefits that tend tocome with passive houses – an orientationand form which tracks the sun will also yield anatural light benefit – the house’s electricallighting requirement balances energy savingwith atmosphere. “The brief from the client wasfor the lighting design not to be dictated purely

by energy efficiency," says lighting designerRocky Wall of Wink Lighting, "but to create at-mosphere and mood using energy efficientlight sources." The design mixes CFLs, LEDs,IRCs and fluorescent bulbs to find the righttones of light for the house’s various spaces.The control system is simplicity itself: con-ventional switching and dimming.

Coming up with a mechanical package for thehouse was another painstaking process dur-ing which various combinations of technolo-gies were modeled and tested – from oil, gasand solar thermal through to the combinationof heat pump and PV panels on which Clau-son eventually settled. Speaking to PassiveHouse Plus just two weeks after moving in,he says that so far, the house has performedexactly as modeled on paper.

“Every nut, every bolt, every screw was thoughtout and put down on paper beforehand,” saysArchie O’Donnell. “That meant that it was adream to go on site. If there was one guidingprinciple that Francis brought to the project, itwas that if you don’t have everything thoughtout on paper beforehand, you’re on a hiding tonothing. Nothing was left to chance, and therewas no ambiguity about what was required.”

For more information on this build visit thewebsite set up by Francis Clauson: www.low-energy-construction.com

SELECTED PROJECT DETAILS Owners: Francis & Brigid Clauson Architect: Zeno Winkens Energy consultant: Integrated EnergyMain contractor: GR8 ConstructionQuantity surveyors: Patrick Breen Structural engineer: Deane Turner Heating engineer: Heat Doc LtdAirtightness & cellulose installer: CliomahouseAirtightness tester: GreenbuildLighting design: Wink LightingBER assessor: 2eva.iePassive house certification: Peter WarmAirtightness system & cellulose insulation:Ecological Building SystemsAirtight plaster: GyprocWindows & doors: True WindowsInsulation: Isover/Kingspan/XtrathermCavity insulation installer: Bunclody InsulationsThermal breaks: Quinn LiteHeat pump: Heat Pumps IrelandHeat recovery ventilation: VersatileKitchens: Andrew RyanInteriors: Doyle Design

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PROJECT OVERVIEW:

Building type: 359 sq m bungalow built totake in the panoramic views stretching to over30 miles and to maximise the solar gain.

Location: Bunclody, Co Wexford

Completion date: December 2012

Budget: not disclosed

Passive house certification: certified

Space heating demand (PHPP): 13 kWh/m2/yr

Heat load (PHPP): 10 W/m2

Airtightness: 0.54 ACH at 50 Pa

Energy performance coefficient (EPC): 0.099Carbon performance coefficient (CPC): 0.091BER: A1 (14 kWh/m2/yr)

Thermal bridging: great attention to detailthroughout the build including first three coursesof Quinn Lite blocks on all rising wall to reduceheat loss to the ground, very detailed windowand door installation detail with PIR insulatedreveals, thermally broken windows, slopingroof to wall join to ensure continuous thermalenvelope

Airtight layer: Gyproc Airtite Quiet plasterapplied to inner leaf block work. Pro Clima sys-tem including Intello membrane to ceiling andtapes at all junctions and penetrations through-out. Ceiling fixed to metal furring inside airtightlayer to avoid breaching airtight membrane

Ground floor: standard sub floor construc-tion with 200mm Kingspan insulation underscreed. U-value: 0.098 W/m2K

Walls: 100mm regular block, 250mm widefully filled with Ecobead platinum bondedbead pumped cavity insulation and 100mmregular block. U-value: 0.15 W/m2K

Roof: Plaster board / 250mm service cavity/ airtight membrane / 500mm pumped cellu-lose U-value: 0.084 W/m2K

Windows: triple-glazed Passive House In-stitute certified Miratherm windows – with atypical U-value of 0.8 W/m2K

Heating system: Danfoss air to water heatpump with Harp registered SPF of 4.13. Underfloor heating system across the whole buildingwhich has been left open circuit (i.e. no ther-mostats) except for the bedrooms which are keptcooler. Wood burning stove in sitting room

Lighting: a mix of low energy lighting includingCFLs, LEDs & IRCs with dimmers and fluo-rescent bulbs

Ventilation: Passive Institute certified ZehnderComfoair 350

Renewable Electricity: 16m2 solar photovoltaicarray with average annual output of 4.2kW

Green materials: cellulose insulation, alltimber furniture from PEFC certified sources

ph+ 45

In 2005, husband-and-wife Ian and Anne sawan ad in The Scotsman newspaper for a plotof felled land in the hills of the Scottish Bor-ders. They visited the site and fell in love withwhat they saw: captivating light, wooded hills,seclusion, a view over the river Tweed.

By April the following year, they'd bought thesite and hired leading green architects Gaia Groupto design their home. The firm says its focusis building healthy, energy-efficient homes, andthat it aims to avoid the use of heavily processedor polluting materials in its buildings.

Ian and Anne spent much of the next two yearsclearing the site of tree stumps, bracken, rose-

bay willow herb and stones.

Anne jumped headfirst into the design. She hada good idea what she wanted: a timber house ina clearing on the slope, but one that wouldsettle into the site. "Kind of hidden but yet withfantastic views," she says — something that would"have the wow factor but be understated".

But she also wanted the design to incorporatestone – a timber frame house that would riseout of the stonework.

She spent almost three years fine-tuning thedesign with Gaia, and the team ended up with aconcept similar to the one they had started

with — for Ian and Anne this just reinforcedthe feeling that they'd got the design spot on.

But the couple were faced with a decision: whatto build the house with? For many projects thatPassive House Plus features, this often comesdown to a choice between block construction ortimber frame. But prompted by Gaia, Ian andAnne plumped for something a little different.

Conceived by the German engineer Julius Nat-terer in the 1970s, brettstapel is a type of glue-free massive timber construction that has becomepopular in central Europe.

The system is composed of softwood posts that

Scottish Borders home

mixes ecology and efficiency

A stunning location, thoughtful design and a certified passive house: a new home in the wooded hills ofthe Scottish Borders manages to have its cake and eat it too.

Words: Lenny Antonelli

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are connected with hardwood timber dowels.The dowels have a lower moisture content thanthe softwood posts, so over time the dowelssoak up moisture to achieve an equilibrium,expanding and locking the posts together tocreate a load-bearing system. Brettstapel useslow grade timber that would otherwise be un-suitable for use in construction.

Gaia Group designed the UK's first brettstapelbuilding in 2009 — Acharacle Primary Schoolon Scotland's west coast. Brettstapel had beenused in Ireland on Navan Credit Union, a pioneering,regulation-bending eco building completed in 2005by Paul Leech: Gaia Ecotecture. As the namesuggests the Irish practice are connected to �

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Gaia Group via the loose-knit association ofarchitects Gaia International.

But Gaia Group didn't just convince the coupleto build a brettstapel house, they persuaded themto build a passive one too.

"The passive house targets were simple toachieve using the brettstapel system, whichwas developed within a culture where high buildquality is taken really seriously — unlike in theUK," says Prof. Sandy Halliday of Gaia Group.

She says that glue-free brettstapel contributesto a healthy indoor environment and locks up

carbon too. But because it's not yet manufac-tured in the UK, it's still expensive.

"We'd never heard of passive house or anythinglike that," Ian says. But Anne loved the simplic-ity of the concept, adding: "What I liked about theidea of a passive house was that instead ofhaving modern ways of generating energy, itwould just save energy by being well insulated."

Gaia took the couple on a tour of passive andbrettstapel buildings in Austria. They contin-ued clearing the site in 2009 and 2010, andstarted planting native bulbs and trees to sup-plement the naturally regenerating birch.

Local contractor Rodger Builders laid thefoundations late that summer, and in Novem-ber Austrian brettstapel specialists Sohm ar-rived to the Scottish Borders.

But the project hit a snag: while seclusion waspart of the site's appeal, getting lorries up thetrack to it proved tricky. When the snow arrived,one of Sohm's lorries got stuck and almost slippedinto a neighbour's garden. The lorry was eventu-ally set free, but Ian and Anne needed a newway to get the brettstapel panels to the site.Luckily the local shopkeeper stepped in, allowingthe lorries to unload in his car park, from wherea tractor trailer took the panels to the site.

Just six weeks later the house was up, air andwater-tight, and Ian and Anne could walk aroundthe bare rooms. The Austrian team worked through-out the snowy winter. "The Austrians were work-ing 12 to 14 hour days, there was snow all overthe place and the daytime temperature was �

“What I liked about the idea ofa passive house was that insteadof having modern ways of gener-ating energy, it would just saveenergy by being well insulated.”

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sometimes below -15C. Nobody else wasworking but the Austrians just got on with it,"Ian says.

The finished house is a testament to the yearsof design work, and the team's attention to detail.While the house is fairly big, it still manages tocomplement its wooded, hilly setting rather thanobtrude from it. And it's seriously green too.

The walls are insulated with 340mm of Steicoflexwoodfibre insulation, which is made from low-grade wood fibres that are bound togetherwith tree resin. The internal sheathing board

serves as the main airtightness layer.

"The challenge was simply ensuring that oncewe had the primary structure tested and passedthat we did not undermine it during the fit outphase," Gaia's Sandy Halliday says of meet-ing passive house airtightness standards.

The roof, which is topped with soil and plantedwith native wildflowers, was also constructedwith brettstapel and insulated with 360mm Ste-ico woodfibre. The ground floor features 260mmof Steico above the concrete slab too.

Continuing the devotion to timber, the windowsare triple-glazed, timber aluclad units, built andfitted by Austrian manufacturer Bohler Fenster.

And there's really not much else to it. This isa project that epitomises the simplicity that isat the heart of the passive house standard:build a high-quality envelope, orientate prop-erly, make it airtight and insulate it well.

A heat recovery ventilation system extracts stale airand pre-heats cool, incoming fresh air. If Ian andAnne need it, they can turn on a small 1.6kWelectrical heating element in the ventilation �

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system to boost the temperature of incoming air.

They also have a wood burning stove in thelounge, but find the house gets too hot if theyuse it. "The stove is more for comfort and effect,"Ian says. A small solar thermal array helps toprovide them with hot water too.

Overheating is more likely to be a problem thancold. To combat this, there’s a brise soleil overthe big south-facing window in the atrium, plusbalconies that overhang windows in the kitchenand south-west bedroom, and external blindsfor the lounge and south east bedroom. The couplesay the summer of 2012 wasn't much of a testfor overheating, but they survived comfortably.

Gaia are carrying out a two year evaluation ofthe house's energy performance. But the awardsare already rolling in. In June 2012 the housewon the Scottish Home Award for ArchitecturalExcellence. Not long after it was certified by

the Passive House Institute — the plaque toprove it now hangs just outside the front door.

SELECTED PROJECT DETAILSArchitects: Gaia ArchitectsContractor: Rodgers Buildersbrettstapel system: Sohm HolzbautechnikStructural engineer: Harley HaddowQuantity surveyors: Ralph Ogg & PartnersGreen roof: IKOGrass seeding: Var ScotiaWindows and doors: Bohler FensterRoofing: AIM DevelopmentsM&E engineer: Mott McDonald FulcrumSolar thermal: BaxiConsulting engineer: Sohm HolzbautechnikCladding contractor: Abbey TimberFlooring: Solus CeramicsLighting consultants: Mott McDonald FulcrumInsulation: SteicothermHeat recovery ventilation:Sustainable Homes ScotlandInternal woodwork: Real Wood StudiosStonework: Grant Morrison Stonecraft

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PROJECT OVERVIEW:

Building type: 297 square metre detachedpassive house that occupies a previously woodedarea on a steep east-facing slope. Constructedfrom brettstapel, a glue-free form of massivetimber construction.

Location: Scottish Borders

Completion date: 2011

Budget: not disclosed


Space heating demand (PHPP): 14 kWh/m2yr


Primary energy demand (PHPP): 109 kWh/m2/yr

Airtightness (at 50 Pascals): 0.5 air changesper hour

Energy performance certificate (EPC): B(81) — the architects told Passive HousePlus that they have identified errors with theEPC that render it incorrect.

Ground floor: 40mm slate finish, followedunderneath by 13mm Fermacell, 18mm tim-ber sarking board, 120m Steicoflex woodfi-bre insulation, 140mm Steicoflex woodfibreinsulation, vapour barrier, 150mm reinforcedconcrete slab. U-value: 0.145 W/m2K

Walls: Timber cladding (rainscreen) on battensexternally, followed inside by timber sheath-ing board, 340mm Steicoflex woodfibre in-sulation, another timber sheathing board,80mm diagonal Dubelholz brettstapel panel.U-value: 0.12 W/m2K

Roof: 80mm top soil externally, followed un-derneath by 360mm Steico Isorel plus insu-lation, bituminous layer, 19mm plywood, 55mmangled Steicotherm woodfibre insulation,180mm diagonal Dubelholz brettstapel panel.U-value: 0.08 W/m2K

Windows: Bohler Fenster boe_classic +timber aluclad triple-glazed windows withChromatec Plus spacers. Frame U-value:0.86 W/2K. Glazing U-value: 0.6 W/m2K.

Heating system: 1.6 kW electric heating el-ement in HRV system. Cylinder with 6 kWelectric immersion element as well as a coilfrom the two evacuated tube solar waterheating panels situated on the roof (5.6 squaremetres), producing approximately 2 MWhper year.

Ventilation: Paul Novus 300 mechanicalheat recovery ventilation system.

Other green features: The previouslymonocultural forest environment has beenextensively re-planted throughout along witha pond and a sedum roof has allowed thereintroduction of native plant species, to en-hance the biodiversity of the site. The bird andanimal life is now significantly more diversethan was the case on the mono-cultural sitethat the house and gardens replaced. Ex-ternal cladding, fittings, furniture and manyother elements have been built from materialslocal to the house.

(above) a custom-made brettstapel panel being man-ufactured in the Sohm Holzbautechk factory in Austria;a construction detail reveals an elegantly simplebuild approach

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Wicklow housecomes close to passive

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With a target as exacting as the passivehouse standard, circumstances can con-spire against meeting every criteria. Archi-tect Sam Mays describes a Co Wicklowhome that hit every passive target exceptone when the builder went bust.

Every project has a story to be told about it. This one islonger and more tortuous than most.

Our clients, Simon Kennedy and Jenny Howe, had bought asite just south of Glen of the Downs in Co Wicklow, a longnarrow plot of land occupied by a small bungalow. It wasassumed that any replacement house would also have tobe single-storey and we agreed a design that duly receivedplanning permission. My mind wasn’t quite at rest, though.I came up with a proposal for a two-storey house that I feltwas a much better – and far more efficient – design and sug-gested we make a fresh planning application. Simon andJenny agreed and the two-storey house in turn receivedpermission.

The excellent envelope/volume ratio of the compact two-storey scheme meant that it became possible to considermaking it a passive house. Having just completed a certifiedpassive house in the Dublin mountains nearby (featured inConstruct Ireland August/September 2011) we were famil-iar with the issues involved and we developed, detailedand specified the project accordingly. The design lent itselfto timber frame construction and we put the project out totender to four teams of contractors and frame manufactur-ers. The winning contractor – renowned amongst architectsfor the quality of his work – made his frame in-house andwas thus able to offer a one-stop-shop service that seemedvery attractive. His panels were fully finished in the work-shop, complete with windows, wiring and internal and exter-nal linings, so they arrived on site ready for assembly; or atleast, that was the idea�

The first problem was weather. Erection of the shell washalf-complete when what turned out to be the long cold win-ter of 2010 set in, rendering work nigh-on impossible for sev-eral months. Construction resumed in the spring, the shellwas completed and for a short period everything went well.However, progress slowed to a crawl, eventually a stand-still, and it became clear that the builder was in deep fi-nancial trouble. He finally went into liquidation in November2011. This was the nightmare scenario; we were left with aproject about 85 to 90% complete and many months be-hind schedule. We decided to finish it ourselves, trying tokeep the trades and subcontractors who had alreadyworked on the house on-board so that we could work withthem directly.

The subcontractors were cooperative and willing to finishtheir work but it was still a protracted and sometimes frus-trating process. Simon and Jenny were by now livingabroad, which complicated things further, but their attituderemained excellent throughout. It’s interesting to see howpeople react to a crisis and we were blessed to have suchlevel-headed people as clients; calm, rational and sup-portive.

The most unfortunate result of the whole affair was thehouse’s airtightness, which failed to meet the level requiredfor passive house certification. The builder was distractedby his financial difficulties and the airtightness layer’s in-tegrity suffered; smoke tests identified the faults but withthe house now at last complete, Simon and Jenny decidedagainst opening-up to correct them.

Even allowing for this, our as-built PHPP calculations showa specific space heat demand of 14 kWh/m2/yr and a specificprimary energy demand of 47 kWh/m2/yr; so while not thefully-certifiable passive house originally hoped for, it’s a near-passive house that should be very comfortable to live in �

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“While not the fully-certifiablepassive house originally hopedfor, it’s a near-passive housethat should be very comfort-able to live in and cheap to run”

and cheap to run. It has high levels of insulation (roof, wall and floor U-values average around 0.11 W/m2K) and minimal thermal bridging; itsthick polished concrete floors provide thermal mass; hot water comesfrom the sun and a wood-burning stove when needed in winter; rainwa-ter is harvested and filtered to drinking standard for use in basins, bathsand showers. It features a double-height living space around which thewhole house revolves and it has a rich variety of connections to the out-side world; windows and roof light frame views of surrounding gardens,trees and sky, while shafts of sunlight prowl beguilingly around the housethroughout the day. �

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SELECTED PROJECT DETAILSClients: Simon Kennedy, Jenny HoweArchitects: Fitzpatrick & Mays ArchitectsMechanical contractor: Heat Doc LtdAirtightness tests: GreenBuildIndicative BER: 2eva.ieCellulose insulation & airtight tapes in roof:IsocellFloor insulation: Kingspan InsulationAirtightness tapes in walls: IsoverAirtightness membrane: GerbandSheep’s wool insulation: Ecological Building SystemsPlaster board: FermacellOrganic paints: AuroWindows, doors & rooflight: Jens Kuechenmeister

External render: KnaufHeat recovery ventilation: Pure Renewable EnergySolar thermal array: Kingspan RenewablesRainwater harvesting: Molloy PrecastWastewater disposal:Biorock system supplied by TECElectrics: Lawlor ElectricalLighting design: Wink LightingJoinery: Oikos Furniture LtdKitchen: Rhatigan & HickTiling: Gerard BensonPainting: Kelly and ThompsonStone paving: Banagher StonePolished concrete floors: Concrete ConceptsLandscape design: Howbert & Mays

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PROJECT OVERVIEW:

Building type: 189 sq m detached two-storeytimber frame house

Location:Old Downs Rd, Kilpedder, Co Wicklow

Completion date: June 2012

Budget: Contract sum €390,000

Passive house certification: Not submittedfor certification as airtightness test results didnʼtachieve the required level. The figures in thefollowing sections are from our as-built PHPPusing the airtightness test results achieved



Airtightness: 1.45 ACH at 50 Pa

BER (indicative rating): A3 (59 kWh/m2/yr).The client is considering the installation ofsolar PV panels which would affect the result

Thermal bridging: all elements of the envelopewere insulated externally to minimise thermalbridging, as described in the following sections

Ground floor: 100mm polished concrete on200mm concrete raft on 250mm KingspanStyrozone H350R insulation, wrapped up outerface of raft at edges. U-value 0.112 W/m2K

Walls: factory-built timber frame with 80mmwood fibre insulation board externally finishedwith Knauf acyrlic render, over 220 x 60 cel-lulose-filled timber studwork, followed inter-nally with 18mm OSB taped & sealed with VarioMultiTape SL, 50mm service cavity insulatedwith Thermafleece sheep’s wool insulation,and 13mm. Fermacell board on 11mm OSB.U-value: 0.122 W/m2K

Roof: Protec glass fibre waterproofing layeron 240mm Kingspan TR27 insulation on vapourcontrol layer on 18mm OSB deck, ex 38 x 38tilting fillets, 220 x 60 timber joists, followedunderneath by Gerband SD2 Control air-tightness membrane & Isocell Airstop tapes,50 mm service cavity and 12.5mm plaster-board ceiling. U-value: 0.097 W/m2K

Windows: Nestle Climate Window HAtriple-glazed aluminium-clad timber windowswith argon filling. Overall U-value: 0.74 W/m2K

Heating system: 60 Kingspan Thermomaxsolar vacuum tubes and Olsberg Tolima AquaCompact 10kW room-sealed wood-burningstove with back-boiler (70% of stoveʼs heatoutput goes to hot water) supplying underfloorheating and 500 litre combi tank

Ventilation: Paul Focus 200 heat recoveryventilation system, Passive House Institutecertified to have heat recovery rate of 91%

Lighting: a mix of low energy lighting in-cluding CFLs, LEDs & IRCs with dimmers

Green materials: Fermacell dry lining board;cellulose, sheep’s wool and wood fibre in-sulation; Auro organic paint. FSC certifiedEuropean Oak used for all joinery and timberflooring, finished in Osmo Polyx white oil

Landscaping: all boundaries planted with na-tive hedging species of hawthorn, hazel and holly.Green manure crop of two seeds of clover mixedwith an ornamental crop of wildflower seedssewn to improve disturbed soil following build-ing works. Edible landscaping includes plantingof apple trees, plum tree, pear tree, blueberrybushes and a walnut tree

(above) The double-height main living space around which the whole house revolves

(p57) large windows and roof lights allow plenty of sunlight into the house, while also providingviews of the garden and sky; FSC certified European Oak was used for all joinery and timber flooring

(p55) this timber frame house is a compact and simple design which made it easier and more cost-effective to aim for the passive house standard

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A central factor in the success of the GreenBase project in St Helens, Merseyside wasthe fact that the client bought into the passivehouse idea at a very early stage.

Simmonds Mills Architects tendered for thejob just after they had completed the Centrefor Disability Studies, a building in Essex thatachieved passive house certification. Duringthe selection process in Merseyside, the ar-chitect brought the client down to the centre toview the passive house approach in action.

Explaining passive principles while actually in

a passive building makes that message somuch more powerful. “They immediately sawthose high levels of daylighting,” says archi-tect Andy Simmonds. “They saw the sunnyspaces. They sensed the air quality and thenthe thermal comfort.”

Simmonds – the current CEO of the UK sus-tainable building association the AECB andco-founder of the Passivhaus Trust – alsogave a presentation on his own home, GroveCottage, the first building in the UK to be cer-tified to the Passive House Institute’s retrofitstandard, Enerphit. “The clients really liked

the presentation as it was relevant to a newbuilding in the middle of a housing estate,” hesays. Given that the same energy saving prin-ciples apply to passive house and Enerphitprojects, the client was taken with the ideathat it’s new nondomestic building might pointto what’s possible with a retrofit.

The client, Helena Homes, is a housing as-sociation and registered charity. Liz Ackerleyof the association explains the need for a newbuilding arose when it was decided to bringthe organisation’s landscape maintenanceservices in house, with the aim of promoting

Sustainabilitywith a passive

One of the UK’s first nondomestic buildings to gain passive house certification, the Simmonds Mills designedGreen Base centre is an embodiment of the environmental ethos it seeks to promote.

Words: John Hearne & Jeff Colley

horticulture and sustainability in the local com-munity. At their 13,000 household QueenslandEstate in Thatto Heath, the company set outto create a building that would harness thisambition.

The site chosen was in an area which Acker-ley terms ‘backlands’ – a landlocked site sur-rounded by houses which had become a dumpingground. The idea was to transform the siteinto community gardens, where various horti-cultural projects could be showcased. Thebuilding at its centre would provide office ac-commodation for Helena Homes’ Green Space

Service, and an information centre for thelocal community.

“We wanted to link into the green agenda inthe context of the building itself,” says Acker-ley. “What we didn’t want was a bells andwhistles approach where we had a bit of thisand a bit of that and a bit of the other. We did-n’t want a high-tech building, but one whichwould demonstrate sustainable principles,something that wouldn’t guzzle a lot of en-ergy. Passive house was the obvious choice.”

The focus wasn’t simply on energy conservation.

The building also had to address the land-scape in which it sat in a way which reflectedthe broader aims of the project.

“They wanted us to come up with a way thata building might fit in and integrate with He-lena’s imaginative edible landscape concepts,”says Andy Simmonds. “We were asked topropose ideas about how the building createda variety of external spaces with different ori-entations, so we paid close attention to theway the building and pedestrian movementon site related to the street, the more privateareas and the existing pathways through thebacklands – suggesting these should be‘green’ corridors.”

Passive building principles always favourtight, non-dispersed footprints simply be-cause they’re easier to heat, but meeting theneeds of the Green Space Service called fora building that wasn’t that straight-forward. Inaddition to ensuring that the building ad-dressed the external landscape in a particularway, the design team also had to allow for thepossibility of extensions in the future.

Passive house specialist M&E consultantAlan Clarke explains that at this stage the de-sign process became a circular one. The ar-chitects came up with a concept, Clarke modelledit on the passive house software PHPP, and ifit wasn’t hitting the targets he reverted withsuggestions about how it might be changed.

“In this case, with a single-storey small build-ing, it was a case of first of all seeing what wecould do about reducing the external area,”says Clarke. “We used PHPP to work out theexternal area to floor area ratios.” He addsthat though the initial model included thesame U-values as the Essex project, a com-bination of fenestration, overall size and cli-mate data kept putting it just out of range ofpassive targets.

Andy Simmonds says that at this stage, there’sfrequently a ‘nervous dynamic’ within the de-sign team. You want to make maximum use ofthe leeway passive house gives you, but youdon’t want to jeopardise certification by stray-ing over those strict limits.

“You can’t guarantee that your M&E person isgoing to do PHPP in exactly the same way asthe actual PH certifier,” he says, “so we spoketo the certifier and the general advice is just makesure you’re well in. Make sure you’re well inbelow that 15 KWh/m2/yr.”

Once it hit construction phase, the project be-came detail-oriented. At the time, Simmondswas refurbishing his own home to the Ener-phit standard. Building on the experience gainedhere and during the Essex job, the design teamwere able to re-use tried and tested details toaddress thermal bridging and airtightness issues.

A shipping error resulted in shallower I-beamsbeing delivered to site than the intended depthof 450mm. In order to keep to schedule andretain the right U-values, the design teamfound a solution in specifying a high perform-ance foam instead of the mineral fibre thathad originally been envisaged. “This causedconsternation in our office because the foamhad very high global warming potential,” saysSimmonds. “We’ve always tried to avoid chemicallycomplex insulants where we don’t need to. �

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And we were very reluctant to be a practice thatnow suddenly had to start using them.”

But because the alternative would have in-volved disposing with the shallower I-beams –which were custom manufactured for thelengths and shapes needed for Green Base –arguably the foam became the most environ-mentally friendly fix. Several of the detailsnow had to be reworked to ensure that air-tightness targets were met without introduc-ing thermal bridges. To avoid too many differentinsulation installers on site the decision wasmade to insulate the Larsen truss walls –which were previously specified with Perime-ter Plus insulation too – with the foam as wellas the roof structure.

Airtightness was achieved primarily throughwhat Simmonds describes as ‘robust’ methods:

a combination of internal plastering, tapesand mechanically clamped airtightness mem-branes, together with the aforementioned PUfoam in the ceiling. Some issues arose whencabling was accidentally rerouted through thewrong area, but remedial action prevented itfrom compromising the passive house stan-dard’s air change target.

Though main contactor Paragon Constructionhad previously built to levels four and five ofthe UK’s Code for Sustainable Homes, GreenBase was the company’s first passive houseproject. “It was quite untracked territory for anEnglish contractor,” says Paragon MD PaulBarrow. “Because it’s a partnered schemewith a local housing association it allowed thecontracts to be conducted in a very hands onway with a collective buy in from the client,the architects and ourselves.”

Barrow says that in some regards the build“was pretty in keeping with the type of stuffwe do – Grand Design type properties. Thein-house build team we have are used toworking to high quality levels.”

The build process itself was fairly straightfor-ward, though Barrow stresses that heavy em-phasis was placed on maintaining the airtightnessthroughout the scheme. Paragon’s mechani-cal and electrical subdivisions installed thebuilding services, enabling tighter control toensure the trades paid attention to the airtightlayer. “It just lent itself well to a passive houselevel of build, given the emphasis that’s re-quired on airtightness,” says Barrow. “Beforewe even set foot on site we had numerousworkshops to educate our site team aboutwhat passive house meant, what it would en-tail and to get full buy in from everyone. That �

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(above) different external insulation strategies were chosen for the building’s timber clad and rendered sections; (below) the reception area with desk featuring re-cycled materials and expressed ventilation ductwork

(p65, top) the raft foundation is insulated with 250mm EPS; (bottom) the external insulation system being applied, including 250mm of platinum EPS

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really paid dividends on site.” A first airtight-ness test before the walls were plastered in-ternally came in at 1 air change per hour. “Wemade sure before we plastered that all thejunctions were taped to be absolutely airtight,”he says. A second test after plastering gave aresult of 0.44 ACH.

Citing former UK Energy Secretary ChrisHuhne’s speech at the 2010 UK PassivhausConference, Barrow says that Paragon see afuture in passive house. “It’s how thingsshould be done in terms of sustainable buildquality,” he says, adding that the companyhas developed designs for passive housewithin budgets for affordable housing schemes.“We’re actively trying to get clients to considerpassive house, whether it’s housing, com-mercial or anything else for that matter.”

Space and water heating is provided via aconventional combi gas boiler, together withconventional radiators. “You give that to a plumber,”says Alan Clarke, “and he'll know what to do.”

Solar thermal water heating was considered,but given the fact that office buildings havelow hot water requirements, it was decidedthat it wouldn’t be an appropriate investment.Ventilation comes via two separate Paul MVHRunits. Again, simplicity was the watchword. Clarkeexplains that two separate systems were cho-sen to avoid any customised control design.

“We steered very strongly away from air heat-ing partly because we see the ventilation asrunning during the day time when loads are

high. On the other hand, from Friday to Monday,while you may still need to put heat into thebuilding, you only need a tick over of ventilation.”

In its first year of occupancy, measured energyusage is actually coming in below forecastvalues. Liz Ackerley says that while the buildingis simply working well, the occupants are highlymotivated and tend to watch their energy use.

“We have a number of other buildings in theassociation. At our head office, you’re either toohot or too cold. That doesn’t tend to happenhere. You don’t get draughts and the air is re-ally high quality. We have hot desks here, andwe’re finding a lot of people tend to come hereto use them. The whole space has quite a calmsort of atmosphere.”

SELECTED PROJECT DETAILSClients: Helena PartnershipsArchitects: Simmonds Mills architectsContractor: Paragon Construction Group Ltd.Quantity surveyors:Client in-house team in partnering contract.Civil / structural engineer: Bob Johnson Structural EngineerServices consultants: Alan ClarkeAirtightness tester: Technology CentreWindows & doors:Internorm Varion, supplied by Frames Direct Ltd.Airtightness products: KloberInsulation:Wetherby render system & Jablite & WalltitePlasterboards : FermacellOrganic paints: OsmoHeat recovery ventilation: Green Building Store

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PROJECT OVERVIEW:

Building type: 212 sq m detached single-storey non domestic building, raft foundationand blockwork walls with external insulation.

Location: St Helens, North West England

Completion date: October 2011

Budget: £522,000 overall project costs, in-cluding landscape and services.




Primary energy demand (PHPP):117 kWh/m2/yr

Airtightness (at 50 Pascals): 0.44 ACH

Measured energy consumption: (Oct 2011 –Oct2012) Natural gas for heating and hotwater: 21 kWh/m2/yr. Electricity import: 24kWh/m2/yr, PV generation: 24 kWh/m2/yr.On-site electrical consumption estimated at32 kWh/m2/yr)

Thermal bridging: thermal bridge free de-tails, based on AECB CarbonLite guidance.

Ground floor: Raft foundation insulatedwith 200 mm Jabfloor EPS, U-value: 0.175W/m2K (PHPP calculation), 0.13 W/m2K (SAPcalculation. All below U-values are based onPHPP calculation)

Rendered walls: Wetherby render system,on 250mm platinum EPS insulation, on 140mmdense concrete block, with internal plasterfinish: U-value 0.125 W/m2K

Timber clad walls: Horizontal douglas firtimber cladding, on Klober breather membrane,on OSB, timber site-made Larsen trusseswith 350mm full-fill blown PU foam insula-tion, on 140mm dense concrete block, withplaster internal finish : U-value 0.085 W/m2K

Roof: Aluminium profiled roof finish, Kloberbreather membrane, OSB, 300mm timber I-beams with 50mm counterbattens, giving350mm full-fill blown PU foam, 15mm Fer-macell & skim : U-value 0.085 W/m2K

Windows: Internorm Varion windows anddoors; triple and 2 + 1 glazing; overall averageU-value of 0.94 W/m2K

Heating system: Broag Rehema Avanta 28ECO 6-28kW condensing gas combi boiler(SEDBUK SAP2009 efficiency 89.1%) withroom compensated control, ordinary radia-tors. Hot water distribution via small bore ra-dial pipework to minimise draw-off volumes.

Ventilation: Two Paul Novus 300 heat re-covery ventilation units — Passive HouseInstitute certified to have heat recovery rateof 93%. One unit serves general offices andancillary space, other serves meeting roomonly.

Electricity: Solar photovoltaic array onsouth facing roof with monitored output of24 kWh/m2/yr

Green materials: Low VOC Osmo woodpaint and stains. Reception desk made fromrecycled & natural materials. Low waterusage sanitaryware. FSC accredited timbergenerally and cladding timber sourced fromUK woodland.

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A house in south Dublin recentlybecame the first Irish building tobecome EnerPHit certified. ArchitectJoseph Little describes the chal-lenges of meeting the Passive HouseInstitute’s standard for upgradingexisting building.

Deep retrofit is the future, but we’ve a lot tolearn. The term deep retrofit refers to an en-ergy-efficiency upgrade that achieves dramaticsavings on existing use of between 50 to 90%using an integrated approach with attentionpaid to airtightness, summer overheating andventilation – and not just super insulation.

While new buildings can be sequenced tomaximise thermal continuity, airtightness andspeed of construction, several factors compli-

cate the works and impinge upon the per-formance possible in deep retrofits. Sub-optimalorientation and constructon methods, old ris-ing walls, intermediate floors and decorativefeatures of a bygone era – the list is long andformidable. The more of the old fabric that’sstripped away, the more ‘sins of the past’ be-come evident – and the more control is gainedto ensure the desired standard is met. Yet thebuilding becomes less and less an old buildingand if the issue isn’t addressed the associatedembodied carbon emissions can rise significantlyin spite of a great reduction in energy in use.

Though energy costs are constantly rising, theymay still be too cheap to prompt enough own-ers to take the action needed to meet nationalclimate change targets and provide sufficientsecurity against future fuel prices. Highlightingthe value gained in comfort, health and qualitynow – with greater financial security thereafter –will only galvanise so many private building own-

ers. Governments know deep retrofit is the mostsensible approach and they know this needsto be implemented everywhere. Shallow retrofitsare problematic in that earlier measures mayprevent – or have to be stripped-out to facilitate– later measures. If the EU’s building stock isto be made nearly climate neutral by 2050 yetthe building fabric of most buildings is onlyretrofitted every 30-40 years, it’s clear that allretrofits undertaken now should meet the tar-gets and compensate for those buildings thatwon’t or can’t. Philip Sellwood of the UK EnergySaving Trust1 estimates that one dwellingmust be retrofitted per minute – and the inter-ventions done right each time – if the UK’s2050 targets are to be met. Ireland must besimilar. Yet Irish energy efficiency grants endin 2013 and the government is following theUK in obliging energy providers to take a cen-tral role in this space while encouraging energyusers at every scale to get the right works done,and done right. Not an easy task.

Monkstown semi-Dsets deep retrofit example

As scale is a great way to make deep retrofitmore affordable, the authorities could focus onterraces and districts with building types thatallow a collective approach – many in oldersuburbs and disadvantaged areas. Such workcould be used as a key way to reduce our de-pendency on fossil fuels, while aiding communityresilience and alleviating fuel poverty – a chroniccondition that’s under-reported in Ireland. Thisis not to mention the value in upskilling con-struction workers, increasing tax take and en-couraging local innovation in this sector. Anotherchallenge is to carry out retrofits without los-ing the character of traditional buildings andthe districts or urban blocks they’re in2. It’s clearthat deep retrofit to EnerPHit standard or equiv-alent throws up a host of issues. To understandand start to resolve these we need built examples.

Ireland’s first certified EnerPHit

My practice recently completed a good exampleof the issues at the centre of deep retrofittingto a clear standard: a 111 sq m 1950s semi-Din Monkstown, Co Dublin upgraded to the En-erPHit standard, with a 48 sq m extension builtto the passive house standard. The buildinghas just been certified Ireland’s first – and theworld’s fifth – EnerPHit project. The house’sowner Pauline Conway first approached us be-cause we were the first practice to be acceptedinto Éasca – an Irish green building associationthat approves companies with sufficiently strongsustainability credentials. She wanted part-ners in a plan to make her house an educa-tional tool and an example of genuinely sustainableretrofit. The project started on site in April 2011.

While we knew that achieving this standardwould set an important example for ordinarysemi-detached houses, we also wanted to pro-mote healthy ventilation, water conservation andlow carbon forms of construction, as we stronglybelieve energy should not be pursued in iso-lation. Pauline grew up in a remote part of ruralIreland. “Until the age of eight years I lived ina house without piped water,” she says, “wherewe had to carry buckets of drinking water from anearby stream and harvest rainwater for laun-dry”. She therefore gained a keen sense of theimportance of natural resources. Later she spent13 years working in African countries. In Ethiopiashe saw at first hand the horrific impact of re-current droughts which are increasing in fre-quency due to climate change, largely causedby developed countries. She wanted her hometo be an example of genuine sustainability.

The design

Our aim was that from the street the retrofitted,extended semi-detached house would continueto fit into its suburban context, while small el-ements such as the juliette balcony and an-odised rainwater goods would suggest that

something special was within. The rear extensionis more clearly different as it orientates exactlyto south then curves away to frame a dining tablewithin and a deck without.

Sunpipes, roof lights and windows extendeddownwards to become patio doors, a glassscreen between hall and kitchen and an openriser stairs with glass balustrade all contributeto even light distribution throughout the house.All services are clustered in the extension,simplifying services runs. A solar panel facessouth west on the rear roof.

Before and after, values, monitoring

Given the project’s aspirations we establisheda baseline with a before Building Energy Rat-ing (BER), an airtightness test and thermo-graphic study. Architect Helena McElmeel iscarrying out a study pre and post-works aspart of the RIAI 3Twenty10 research project.Despite the more than three hundred thousandpublished BERs there is extraordinarily littleknown about how Ireland’s dwellings actuallyperform and are actually used after retrofit.

We established that the initial airtightness ofthe house was 5.6 air changes per hour at 50pascals. While this seems an amazing valuefor an old house, levels close to this may be morecommon than realised for older buildings thatwere well built and have not been interferedwith. The AVASH study3 of thirty-two socialhousing dwellings in Leinster established an av-erage airtightness for the existing, untouchedhousing stock it studied (mostly from the 50sand 60s) of 7.98 ACH, while those that had beenretrofitted averaged an appalling 13.3. Heatcan be lost quicker through gaps and cracksthan in conduction through insulation, espe-cially in windy countries like Ireland, so it’s veryimportant that baseline conditions are under-stood and improved upon in retrofit work.

The air barrier of the semi-detached house ismostly the original wet plaster. The attic had beenvery carefully-insulated in the 1980s, withnow mostly collapsed mineral wool, and hadbeen carefully re-glazed more recently. Sur-prisingly, for the airtightness value achieved, thetimber floors were suspended: presumablythe underlay was thick and dust-filled!

Low carbon and timber

A key low carbon approach in the project wasusing wood-based products when possible.Using wood in construction ensures that car-bon captured through photosynthesis (becom-ing the very stuff of trees) remains bound-up,and it’s also a great insulant. We love the factthat cellulose insulation was newspapers whichhad been trees: well-read material saved fromburning and landfill.

We used 220mm FSC-certified timber studsfor the extension’s walls, clad internally with 18mmOSB3 as a racking board and airtightnessbarrier, and slabbed externally with 80mmthick Diffutherm woodfibre external wall insu-lation. We then blew cellulose into the resultingcassettes between4. The flat roof was similarexcept that Gutex woodfibre slabs were usedover joists. The main cold roof buildup fea-tured 400mm of cellulose. In all 56 m3 of cel-lulose and 11 m3 of woodfibre were used.

Higher embodied energy – low carbon

response

Before adopting EnerPHit we had intended toinsulate under the suspended timber floor inthe usual manner for retrofits. In moving to �

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Figure 1 – embodied carbon in materials used5

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EnerPHit we realised that the resulting U-val-ues wouldn’t be good enough. In any case asthe insulation depth increased beyond thejoist depth the repeat thermal bridges wouldget worse. Instead we stripped out the joistsand tassel walls, laid a radon barrier on theoriginal subfloor and built up 300mm of EPS300,then poured 150mm of concrete with 70%Ecocem GGBS on top. This gave us a retro-fit floor U-value of 0.11 W/m2K.

Clearly the thermal performance and ability tocontrol quality greatly increased, but the amountof floor and sub-floor materials going to land-fill also increased because of this decision.We knew the use of low carbon concrete, woodfibre and recycled products would compen-sate but it is striking that the EPS300 slab in-sulation had a greater carbon impact thanexpected. Its density means that the amountof EPS contained is much greater. In subse-quent projects it’ll be interesting to see if al-ternative insulants below slab can improve onthat carbon impact, and at a reasonable cost.The embodied carbon of the uPVC windowframes is also worth noting.

Figure 1 should only be considered a rough,incomplete estimate of associated CO2 (equiva-lent) emissions: the impact of the membranes,renders and finishes, for example, are omitted.We deliberately show a few alternatives suchas mineral wool in the attic or brick rain screen(highlighted in red) to illustrate how swappingapproach and specification can allow an equalor better performance, yet less carbon. Welook forward to the imminent publication ofSEAI’s embodied energy and carbon meas-urement methodology and database which shouldmake this kind of analysis, and resulting lowcarbon-focused specification, more commonand more Ireland-specific.

The steel column – a key point thermal bridge

A key technical issue that had to be resolvedwas how to bring the load of the rear corner ofthe first storey to ground in a ‘thermal bridgefree’ way6 once the ground floor walls wereremoved to make way for an open plan spacebelow. Figure 2 shows the column, the wallit’s supporting above and the footing below. Italso shows how the line of thermal continuityand water management are separated at therooflight, minimising thermal bridging and air-tightness issues there.

We worked closely with engineers MaloneO’Regan to arrive at a final solution featuringan unusually large base plate that transferreda uniformly distributed load of the columnonto a 100mm Perinsul Foamglas layer ontoa concrete pad. Figure 3 shows an output froma point thermal bridge evaluation using the newlytranslated Psi-Therm software. Note the tem-perature at the junction of floor and column(19.36C) is only 0.5 K cooler than the floorelsewhere.

Managing airtightness & delivering quality

For this project we ensured that only builderswho had built to an n50 of below 2.5 air changesper hour could tender. We provided a detailedairtightness specification, clear red-lined draw-ings and toolbox talks with technical supportfrom Ecological Building Systems. Prime costsums were allowed against each of three tests:one just after the air barrier had been formedbut before first fix, the second after second fixand the third before practical completion wascertified. Signing the latter certificate was �

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(left) and (p67) the rear extensionorientates exactly to south thencurves away to frame a diningtable within and a deck without

(p66) the externally insulated frontof the new extension & originalhouse are in keeping with the sub-urban context

Figure 2 – detail showing how the upper floor of house is supported and differentiationofweather barrier and insulation continuity at the roof light

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contingent on the builder meeting the design values.

Because the focus on airtightness was con-sistent and clear, and because the builder wasfacilitated and supported to reach the valuethrough the support material and process cre-ated, there was little wriggle room allowed. It’scritical that builders understand this before-hand, price soberly and put their A-teams for-ward. Design teams and clients need to judgethis equally soberly and recognise that skilledteams and great care on site don’t come withbargain basement tender prices. Perhaps know-ing that a project must reach the EnerPHitstandard gives all sides support at the criticaltendering and contract signing stages.

We realised early on during airtightness teststhat there was air leakage through some partsof some of the 18mm OSB3 boards7. To avoida costly variation to the client if new AVCL mem-brane and tape were applied to the boards wecontacted Remmers, a company that deliversconservation and breathability focused treat-ments and plasters. They suggested two roll-on coats of Induline ZW-400 might improvethe airtightness of the boards. We advised theclient and agreed to take a gamble on this ap-proach. Airtightness tester Gavin Ó’Sé wasable to prove that this improved the airtight-ness of the boards.

At the first construction stage airtightness test(an n50 of 3.67 ACH) it was clear that BourkeBuilders had started to move ahead, slabbinginsulated plasterboard at the party wall ther-mal bridges and first fixing. We instructed themto stop until the design airtightness value wasreached. If it’s not reached at this stage, whenthe layers of buildups and number of pene-trations are relatively few and easily accessed, itnever will be. Later tests are to ensure the valueis maintained. There was clearly a learning curveon the specific difficulties of airtightness in retrofits.Diagnostic airtightness tests were crucial inhelping us learn where under-performance wasoccurring and Bourkes took the appropriate cor-rective actions. We graduated from whole housetesting to room by room testing using our hands,anemometers and smoke. It was only after thefourth construction stage test (an n50 of 1.3ACH) that we allowed them to proceed to firstfix as there were a few areas where improve-ments could yet be made unhindered by otherworks. In the end there were seven formal testsduring the project and many more informal testsby the foreman using a Wincon fan. Bourkespaid for the additional tests. Their commit-ment to getting it right was central to theteam’s achievement of EnerPHit certification.

Water conservation

Dual flush toilets, low volume bath and bowls

and sprinkler taps feature. We also worked closelywith Ollan Herr of Reedbeds Ireland on therainwater harvesting strategy. The location oftank and specification changed more thanonce but we were committed to a small grav-ity-fed tank within the building envelope. Herris critical of the current vogue of overly largetanks buried in gardens requiring pumping overtwo storeys or more.

Located in an upper press of a walk-in-wardrobe,the system at Wynberg Park serves an out-side tap and two toilet cisterns only. An out-side leaf filter and two fine filters inside ensurethe water is fit for purpose. Toilet usage typi-cally comprises about 35% of a person’s dailywater demand. By focusing on supplying waterfor this function the size of the tank could bereduced to 450 litres, cutting out the need forelectrically powered UV filtration. Locating thetank below gutter level but above toilet cisternheight meant the system could be gravity fed.Because the tank’s inside the house it requiresno insulation. By using a simple water trap thesupply is airtight. Finally fail-safe measuresensure the tank never overfills or empties. Weliked the simplicity and technical elegance ofthis approach.

Moving forward

This project contained a range of innovationsfrom timber frame wall system to overall per-formance specification, to rainwater harvest-ing approach. There was lots of learning –some through mistakes. The team got a num-ber of things – such as meeting the EnerPHitstandard – right and can prove it. That itself isa great message for building in Ireland.

The industry needs many more example casesof deep retrofit to a clear standard. All rele-vant bodies need to actively explore the chal-lenges of deep retrofit and community scaleretrofits, and then engage with others in trans-forming the construction industry. If we’re se-rious about the 2050 targets, about reducingour oil and gas dependency and about gen-uine sustainability, we need to make signifi-cant changes in focus, policy and building culturein the next two years.

An extended version of this article is availablefrom the author �

upgrade Figure 3 – point thermal bridge analysis ofcolumn base plate. χ-value = 0.041 W/KNote: air temp. 20C, ambient ground temp. 10C

(above) the stick built timber frame extension being built (above right); OSB3 boards taped together and AVCL membrane connecting to OSB3 in floor above, withsquare tapes where cellulose had been blown in and insulated ducts

Figure 4 – the progress of airtightness tests

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SELECTED PROJECT DETAILS Client: Pauline ConwayArchitect: Joseph Little ArchitectsPassive house consultant & BER assessor:Ann-Marie FallonCivil / structural engineers: Malone O'ReganQuantity surveyors: Walsh AssociatesMain contractor & timber frame:Bourke Builders LtdAirtightness tester: GreenbuildGGBS cement: Ecocem Ireland EPS 300: Kingspan AerobordThermal breaks: Thermal Insulation Distributors LtdOSB3 board: CoillteBreathable sealing coat for OSB3: Remmers Blown cellulose: Ecological Building SystemsCellulose installation: Clioma House External wall insulation system: BaumitDiffutherm external wall insulation:Natural Building TechnologiesBrick slips: Ibstock Brick (Ireland)Windows & doors: Munster JoineryAirtightness products: Ecological Building SystemsGutex woodfibre insulation:Ecological Building SystemsRoof windows: VeluxSun pipes: FakroSolar thermal supplier: Kingspan RenewablesHeat recovery ventilation: Pure Renewable EnergyRainwater harvesting: Reedbeds IrelandFlow Limiters: Armitage ShanksWater conserving sanitaryware:Sandringham Fittings

1The Retrofit Challenge: Delivering Low Carbon Buildings,from Centre for Low Carbon Future and Energy Saving Trust,2011. Available at http://www.energysavingtrust.org.uk2Several EU-funded projects have focused on exactly this,e.g. 3Encult, Susref and Refurban.3AVASH stands for Advanced Ventilation Approaches for So-cial Housing. DW EcoCo were the Irish partners of the threecountry project that ended in 2008. Papers can be found atwww.brighton.ac.uk/avash/4This is very different to the poor practice of slabbing EPS in-sulation outside timber frame which has caused failures inCanada and Sweden. The BBA-approved Diffutherm systemfor timber frame has been extensively tested and simulatedfor use throughout the UK. We believe this is the first timeit’s been used in Ireland.5Green bars show materials used, red bars show materialsand emissions avoided. Concrete values came from EcocemIreland Ltd, woodfibre values came from Natural BuildingTechnologies. All other values taken from Ökobilanzdaten imBaubereich 2009/1 jointly researched and published inSwitzerland by KBOB, Eco Bau and IPB: www.kbob.ch6 As the Passive House Institute and indeed many EU mem-ber states measure buildings from the outside, a junction thatthey consider ‘thermal bridge free’ (i.e. <0.01 W/mK) mayhave a higher value when measured from the inside as perUK and Irish regulatory standards7KU Leuven has carried out an interesting study on the air-tightness of OSB boards from eight different manufacturers.They found that even within the same brand variation in air-tightness can occur. It appears that even 18mm OSB3 cannotbe expected to act as an air barrier at these design values.

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PROJECT OVERVIEW:

Building type: 1960s semi-detached dwelling. EnerPHit retrofit to existing and passive houseextension to side and rear.

Location: Wynberg Park, Monkstown, Co Dublin

Completion date: April 2012

Budget: €240k

EnerPHit certification: Certified

Building Energy Rating (BER)

Before: G (494.88 kWh/m2/yr)After: A3 (51.19 kWh/m2/yr)

Space heating demand (PHPP)

Before: n/aAfter: 17 kWh/m2/yr

Heat load (PHPP)

Before: n/aAfter: 12 W/m2

Primary energy demand (PHPP)

Before: n/aAfter: 109 kWh/m2/yr

Airtightness (at 50 Pascals)Before: 5.66 ACHAfter: 0.93 ACH

Original walls: Rendered 215mm concrete hollow block wall. On ground floor (front elevation only)uninsulated cavity wall with exposed brick. All internally plastered. Average U-value: 2.40 W/m2KRetrofitted walls: Mineral render finish on 150mm Baumit Platinum EPS EWI on existing. On frontground floor cut-down brick slips to match existing brick over external wall insulation & cavity filledwith platinum bonded blown bead. Renovated and extended existing wet plaster finish used as mainair barrier. In rooms adjoining party wall 50mm insulated plasterboard internal wall insulation usedadditionally to minimise thermal bridging. Average U-value: 0.13 W/m2K Extension walls: External render, on 80mm Diffutherm woodfibre EWI with mineral render, on 220mmopen panel timber frame filled with cellulose, on 18mm OSB-3 board, on 50mm Thermafleece PB20sheepswool service cavity, on plasterboard. Taped OSB-3 used as main AVCL. U-value: 0.12 W/m2K

Original roof: Pitched cold roof with 100mm mineral wool insulation between joists. U-value: 0.40 W/m2KRetrofitted roof: 350mm cellulose blown between and over joists, on Intello membrane AVCL, onplasterboard. U-value: 0.10 W/m2KExtension pitched roof: Pitched roof as per retrofitted roof. Extension flat roof: Double butyl membrane on double layer of marine plywood, on 50mm venti-lated air gap, on Solitex membrane, on 24mm Gutex woodfibre sheathing board, on 250mm timberjoists filled with cellulose, on 18mm OSB-3 board, on Intello membrane AVCL, on 50mm insulatedservice cavity, on plasterboard. U-value: 0.13 W/m2K

Original ground floor: Uninsulated suspended timber floor over ventilated undercroft with tasselwalls and sub-slabRetrofitted ground floor: Existing sub-slab under 300mm Aerobord EPS 300, under 150mm concreteslab with 70% GGBS. U-value: 0.11 W/m2KExtension floor: Clause 804 aggregate with radon sumps under, radon barrier under, 400mmAerobord EPS 300, under 150mm concrete slab. U-value: 0.08 W/m2K

Original windows & doors: double-glazed, air-filled PVC windows and doors to most of house. U-value: ~ 2.80 W/m2KNew triple-glazed windows and doors: Munster Joinery triple-glazed Future Proof uPVC sashwindows. U-value: 0.80 W/m2K Roof windows: Velux GGL/GGU thermally broken triple-glazed roof windows with thermally brokentimber frames. U-value: 1.9 W/m2K

Space heating & hot water system

Before: 20 year old oil boiler (circa 70% efficient) serving radiators in every room and two open fires.After: The primary heating involves post-heating the HRV supply air. A 12kW modulating gas boilerproviding back-up heat to a network of three small radiators, and two towel radiators zoned sepa-rately due to daily use. A 3.2m2 Kingspan Thermomax HP 200 3M2 evacuated tube array on mainrear roof facing south-west supplies hot water to a 300L 100mm factory-insulated cylinder (with triplecoil allowing additional future heat source). A 12kW modulating gas boiler supplies the shortfall.

Ventilation

Before: rapid ventilation supplied by windows, no trickle vents, extract via pull chord unit in kitchenand chimney in living roomAfter: Paul Novus 300 VL (Passivhaus certified) HRV system, with recovery rate of 92.4% as installed.Primary air ducts are limited to 0.5m long with 100mm insulation

ABOUT THE AUTHOR

Joseph Little is the principal of Joseph Little Architects and Building Life Consultancy. Heis a strong advocate of the use of scientific principles, better evaluation tools and rigour indesigning and constructing new build and retrofit. The practice was an early adopter of lowenergy design principles. The consultancy is the Irish co-operation partner of the FraunhoferInstitute for Building Physics for use and development of Wufi software, and the promotionof numerical hygrothermal assessment in Ireland. He provides training courses within theRIAI and in industry. He has written and lectured on a wide range of construction, retrofitand evaluation issues in the UK and Ireland.

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A community centre in a deprivedarea of north London has becomeone of the few buildings in the UK& Ireland to get passive housecertification with a renovation.


Most architects tasked with turning a run-down,19th century building into a modern commu-

nity centre would do the obvious thing: knockit and rebuild. A different fate was chosen forMayville Community Centre.1

This concrete-framed, brick-clad building inIslington was originally a generating stationfor London's tram network. The MildmayCommunity Partnership saved it from derelic-tion in 1973 — demolishing their home wasnot an option.

"There are quite a few longstanding memberswho absolutely adore that building," says centremanager Teena Phillips.

The centre does most of the things you'd ex-pect from a community centre: runs classes,helps local traders, connects kids with oldercitizens, and provides a space for communitygroups, from an over 50s social club to child-care and singing groups. Mildmay is one ofthe most deprived areas in London.

The building was "old, dingy, dark, cold" before,Teena says. Energy bills were sky high, therewas no insulation, and much of the buildingwas unusable.

So passive house experts Bere Architects set

Islington centre

gets award-winning passive

out to do what many others have failed toachieve: full Passive House Institute certificationwith a retrofit.

Enerphit certification — the Passive HouseInstitute's less onerous standard for retrofitprojects — didn't exist when the renovationwas first mooted, so it was either full certifi-cation or nothing.

Architect Justin Bere says he proposed goingfor passive as "the most reliable means to makethe building warm and comfortable with minimalenergy bills".

Hitting passive house targets for airtightnessand thermal bridging can be particularly diffi-cult with an old building.

"Enerphit hadn't been devised as a concept atthe time and we didn't feel particularly challenged.We had confidence that with knowledge, diligenceand collaboration we would succeed," he says.

Bere Architects decided to wrap the walls inPermarock EPS external insulation, which en-velopes the building and cuts out thermalbridges — gaps in the insulation where heatcan escape, such as where internal floors

meet the external wall. Because the buildingis free standing, it was possible to dig downand insulate around the basement too. Newbalconies and steelwork on the south facadewere also thermally isolated from the building.

The team wrapped the roof in a DuPont Tyvekmembrane for airtightness and vapour con-trol. For the walls, the parge coat used to glueand mechanically fix the external insulation tothe external walls also acts as the airtight layer.

The trickiest airtightness detail was over theold roof trusses, but Justin Bere says it was �P

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easily dealt with by planning ahead. "Prepa-ration in design and construction is all that'sneeded," he says, "care rather than any particu-larly unusual level of cleverness."

Bere Architects designed a new zinc pitchedroof which was filled with 400mm of Rockwoolinsulation, while the two flat roofs were insulatedwith 300mm of Foamglas, a type of cellular glassinsulation. Each was also topped with soil andplanted with native wildflowers to boost biodi-versity and reduce rainwater runoff.

Insulating under the ground floor wasn't possible,so the team did the next best thing — exter-nally insulated the walls right down to thefoundations to cut out thermal bridging, andinstalled 75mm of Kingspan phenolic insula-tion on the basement's concrete raft.

They ripped out the building's draughty oldsingle-glazing and installed new triple-glazed,thermally broken Passive House Institute cer-tified Bayer windows and doors, bracketedonto the face of the external walls to keep levelwith the external insulation and taped for �

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(above) all viable space for solar PV is exploited, including the roof of the single storey extension; (below) the new zinc pitched roof, filled with 400mm of insulation;(bottom left) external insulation was applied to the walls right down to the foundations to reduce thermal bridging; (bottom right) the renovated centre allowsmembers of the community to meet and socialise in a comfortable environment

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airtightness. Triple-glazed roof lights were putin too — again with well-worked details for air-tightness and cold bridging.

The building was also kitted out with renew-ables —a new Viessmann ground sourceheat pump replaced the old gas boiler.

When heating is needed, it's delivered by reg-ular old radiators. These were deliberatelyoversized, which means they can deliver enoughheat while running at a lower-than-normaltemperature of about 45C. This makes themmore compatible with a heat pump, which aremore efficient when delivering heat at lowertemperatures. Three square metres of solarthermal panels on the roof also help generatehot water for the building.

The centre also has a huge array of electric-ity-generating Sharp solar photovoltaic (PV)panels on the roof— 77 panels over an areaof 127 square metres.

"At the time it was one of the biggest oneswe'd done," says Ollie Davenport of PV sup-plier The Energy Warehouse. "It seems to beworking well, it's producing what it should beproducing."

Lighting is a mix of low-energy CFLs and con-ventional fluorescent tubes. Though anyone

can turn the lights on with a switch, they dimautomatically when there's enough sunlightgetting in, and shut off if a room is empty.

Rainwater harvesting systems collect rain thatfalls on the roofs, filter it and deliver it to toiletsand for the garden and food growing.

Swift, sparrow, wren and bat boxes have alsobeen installed within the external insulation.

As with all certified passive buildings, heat re-covery ventilation extracts stale air and usesit to pre-heat incoming fresh air. Anecdotally,it seems to be making a big difference inside.

Centre manager Teena says the building hasa "light, airier feeling to it" now. Since the renova-tion, she says there's no longer a 3pm rush forcoffee. She doesn't pick up as many colds be-fore either, she says, or feel as tired.

"Working in that building [before] was cold, dampand dingy," she says. "The office environmentdoes play a big part in illnesses and that I think."

To create more space, Bere designed a newentrance block and dining area. The team ex-cavated around the basement and created asouth-facing light-well here that delivers sun-light and ventilation, turning it into a functioningworkspace. �

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(above & below) meticulous cold bridgingdetailing around the south-facing roof lights;(bottom) thermal imaging reveals a markeddifference between the upgraded centre andthe surrounding buildings

ph+ 79

Teena says before the building was alwaystoo hot or too cold, but now she's never evenaware of the temperature — it's just comfortable.

"This is really our first year getting used to thebuilding and everything," she says.

Teena wants to use the building as a tool toeducate the local community about buildings,energy and the environment, and the centrehas teamed up with University College Lon-don on a project that aims to do just that.

Before the renovation the building was consum-ing 581 kWh/m2/yr — the renovation is esti-mated to have cut this to just 120 kWh/m2/yr,and less just 10% of that is for space heating.The building's net CO2 emissions are now al-most five times less than they were before therenovation. And the running cost data looks verypromising too.

The ground source heat pump is the only spe-cific heating source in the building. For the 12months from January to December 2012 thetotal spent on electricity to run the heat pumpwas £328.20 – and even that is a worst casescenario figure, based on calculations usingthe higher day time rate of electricity. This totalexpenditure has been worked out on actualmetred usage from the heat pump and doesn’ttake into account electricity from the solar PVarray. As the PVs provide approximately 36%of the total building’s energy consumption, it’sestimated that the actual cost to heat the 665sq m centre in 2012 was nearer £210.

Bere Architects even moved their own officesinto the building, which has won a plethora ofawards2. "I'm constantly amazed at how warmand comfortable the building is in winter, andhow cool and comfortable in summer with little orno effort by the users, and with tiny amountsof energy input," Justin Bere says. "Passivehouse works better than I dared hope."

SELECTED PROJECT DETAILS Clients: Mildmay Community PartnershipPassive house consultant: Bere ArchitectsPassive house certification: BREStructural engineers: ConisbeeM&E engineers: Alan ClarkeQuantity surveyor: e-Griffin Consulting LtdPost occupancy evaluation partner: BSRIAAirtightness tester: Gaia AldasSbem calculations: XCO2 EnergyLighting design: GIA EquationsGreen roof designer: Dusty GedgeMain contractor: Buxton Building Contractors LtdExternal insulation system: PermaRock ProductsInsulated foundation system: Kingspan InsulationMineral wool insulation: RockwoolRigid board insulation: FoamglasWindows:Bayer Windows, supplied by Doublegood Windows Openable roof windows: Velux Fixed roof windows: Isaacs Glass Co. LtdAirtightness tapes:Tremco Illbruck, supplied by BayerBreather membrane: DuPont TyvekThermal breaks: SchöckRainwater harvesting:Aquality Trading & ConsultingSolar PV: The Energy WarehouseHeat pump & Solar thermal: Viessmann LtdHeat recovery ventilation:The Green Building Store

1The building was recently renamed Mildmay CommunityCentre in recognition of the centre’s growing significance inproviding community services for the whole of the IslingtonMildmay ward2In 2012 the Centre won the retrofit award at the UK PassivhausAwards, the building performance award at the ConstructingExcellence in London and the South East Awards and theleisure award at the Greenbuild Awards. It had won the bestpublic building award at the 3R Awards in 2011.

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PROJECT OVERVIEW:

Building type: 665 sq m Victorian solid masonry building, originally housing electricity generatorssupplying the London tram network. Now a community centre.

Location: Islington, north London

Project budget: £1.6m

Passive house certification: full certification achieved

Space heating demand:

Before: 581kWh/m2/yr if 21oC maintained in winter, but in reality that was not affordable, so 272kWh/m2/yr with low internal temperatures in winter After (PHPP): 12 kWh/m2/yr

Primary energy demand (PHPP):

Before: not calculatedAfter: 120kWh/m2/yr. Of this only 12kWh/m2/yr) will be used for space heating, with an approximateannual cost of £600

Energy performance certificate (EPC): not calculated

Heating bills:

Before: Gas bills of £5900 per annumAfter: £328 (Jan-Dec 2012) calculated based on meter readings from heat pump - or an estimated£210 taking into account solar PV contribution

Airtightness (at 50 Pascals): 0.43 ACH

Existing building walls:

Before: 450mm uninsulated brickworkAfter: (above ground) 290mm Permarock EPS external insulation, 10mm render finish, U-value 0.116 W/m2K.(below ground) 200mm external XPS insulation to existing brick walls. U-value: 0.154W/m2K

New extension walls: single-storey blockwork wall construction, 15mm internal plaster, 215mmblockwork, 290mm EPS insulation, 10mm render, U-value: 0.119 W/m2K

Pitched zinc roof: 15mm plasterboard, 18mm OSB, 300mm Rockwool Flexi fitted between the struc-tural timbers, 100mm Rockwool Rockfall overlay board with breather membrane, Tyvek Supro in-stalled on top, 50mm timber battens, 20mm standing seam zinc roof finish on 20mm timber substrate.U-value: 0.109 W/m2K

Green roof: high level flat roof: 300mm Foamglas insulation on existing concrete roof slab with as-phalt covering and 100mm soil and meadow planting. U-value: 0.130 W/m2K

Low level flat roof: 300mm Foamglas insulation on new timber roof structure with 20mm asphaltlayer and 100mm soil and meadow planting. U-value: 0.131W/m2K

Floor: New entrance floor slab 300mm Foamglas insulation and concrete slab. U-value: 0.129 W/m2K

Existing basement floor slab 300mm existing slab with 80mm Kingspan insulation and floating floor.U-value: 0.256 W/m2K

Windows & doors:

Before: single-glazed, draughty windows and doors. New windows: Triple-glazed Bayer Passive House windows with thermally broken timber frames. U-value: 0.6 W/m2K

New openable rooflights: Velux, electronic, timber framed, triple-glazed passive house units.

New fixed rooflights: Isaacs Glass Co, triple-glazed glass units. U-value: 0.9 W/m2K

Entrance door triple glazed Bayer Passivhaus automatically opening glass with thermally brokentimber frames U-value 0.85 W/m2K

Airtightness:

Airtightness sealing tapes between window frames and internal airtightness layer /vapour controlmembrane, and window frames and first floor external breather membrane.

Airtightness and vapour control layer to provide continuous envelope around building envelope inplan and section. Airtight layer for walls is parge coat used to fix insulation to external walls. Airtightlayer for roof is Tyvek membrane.

Heating system:

Before: industrial gas boilerAfter: 8.4kW Viessmann Vitocal 300-G ground source heat pump with 140m double pipe trench

Ventilation:

Before: no ventilation system, reliant on infiltration and opening of draughty windows for air changes.After: Paul Maxi 2000

Green materials: (to all internal surfaces) untreated softwood used throughout, birch plywood, naturallinoleum floor finishes.

Microgeneration: 126m2 of photovoltaic panels 77 no.NU235E1 Sharp Panels 235W = 18kWp

Solar thermal: 3m2 Viessmann Vitosol 200 solar array

ph+ 81

Is the green new deal dead — or was it evereven born? After western economies tankedin 2008 the idea of green economic stimulus hadits heyday.

Making our buildings drastically more energyefficient was at the heart of the plan. We couldkill five birds with one stone: cut carbon emis-sions, make homes warm, slash energy bills,create jobs and kick start sluggish economies.

In the US, then presidential candidate BarackObama promised to create five million "greenjobs". His first stimulus bill as president evenbacked this up with $90 billion for green projects.

The British prime minister Gordon Brown saidthe economic crisis was "an opportunity to tackleour over-dependence on oil and to meet ourthree interlinked objectives – energy security,climate change and job creation – together."

His successor David Cameron took over prom-ising the "greenest government ever." In 2010,the Irish government announced plans to up-grade one million buildings within a decade1.

But progress has been stagnant. The Inter-national Energy Agency says 80% of the"economic potential" of energy efficiency inbuildings remains untapped2.

In Europe we renovate just one per cent of our

buildings each year3. "This is just not enough,it's not ambitious enough for the future," saysAdrian Joyce of Renovate Europe, a retrofitcampaign backed by big companies in the en-ergy efficiency sector. "We're just not doingenough renovations, and the renovations wedo are not deep enough."

England is now without a government-fundedhome insulation programme for the first timesince 1978. The coalition government has killedWarm Front, which provided insulation and heat-ing grants to low income households. Scotland,Wales and Northern Ireland continue with theirequivalent schemes.

One of the programmes that has replacedWarm Front is the Green Deal, which offersretrofit loans that homeowners pay off throughtheir energy bills. The programme's 'goldenrule' aims to ensure that savings on energybills equal or outweigh the loan repayments(though this is not guaranteed).

"The golden rule is rationally a very goodidea, but in reality is not going to work," saysAdrian Joyce. "If you're only going to considerthe rate of payback as the sole criterion,you're almost always only going to have shal-low investments."

Even the UK Department of Energy and Cli-mate Change's own assessment expects the

number of loft and cavity wall insulations toplummet by 83% and 43% respectively in thefirst year of the Green Deal and its sister pol-icy, the Energy Company Obligation4.

Financed by energy companies, the ECO willfund energy efficiency measures in low incomehouseholds and harder-to-treat properties.

But energy companies will inevitably gatherthe funding by adding to fuel bills. This will makethe scheme regressive, says Andrew Warren ofthe Association for the Conservation of Energy.

"Poorer people will end up paying a greaterproportion of that and will not necessarily bebenefiting," Warren says. Essentially, all bill-payers will pay the same tariff regardless ofincome, and while all fuel poor bill payers willhelp fund the scheme, not all will benefit fromenergy upgrade measures.

The UK government is obliged to eradicatefuel poverty in England and Wales by 2016,under a law passed in the early days of TonyBlair's government. But this is now virtuallyimpossible: research suggests there are nearlyeight million people in fuel poverty in England,and this is expected to rise5 as the govern-ment cuts funding to tackle it6.

In Ireland, retrofit is in limbo. The current gov-ernment came to power in 2011 promising to

HOW TO RESCUERETROFIT

Progress on retrofitting Europe's building stock is sluggish, but there is a way out of the mire.


Image:

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double funding for home energy efficiency andrenewable energy until 2013, and to insulate allpublic buildings in the state via pay-as-you-save.

Neither commitment has materialised. Thegovernment has cut its Better Energy heatingand insulation grants twice since 2011. Itslashed the programme's budget from €76min 2012 to €50m in 20137, but has promised anew €35m "energy efficiency fund".

The number of Better Energy measures ap-proved — a good indicator of the number ofapplications— fell from over 160,000 in 2011 toless than 65,000 in the first 11 months of 20128.

The Better Energy Warmer Homes scheme,which funds energy efficiency upgrades to thehomes of the elderly and vulnerable, upgradedover 37,000 houses in 2010 but only around14,000 last year (including about 2,000 in anew area-based pilot that aimed to tackleclusters of houses)9.

Energy minister Pat Rabbitte recently told theIrish Times that while 5,500 people were em-ployed due to government retrofit programmes in2011, the figure for 2012 could be up to 1,000 less.10

Ireland's goal is to upgrade one million build-ings by 2020, almost all of which will bedwellings. But the rate of activity needs to pickup because the country is currently upgrad-ing 50,000 to 60,000 homes a year, accordingto the National Economic and Social Coun-cil11. The vast majority of upgrade measuresare shallow ones too, focusing heavily on lowcost measures like cavity wall and loft insula-tion. NESC says there is an "urgent need to bringforward new measures" to meet the targets.

So how do we turn things around? Two recentreports illuminate the way forward. Oxford Uni-versity’s fuel poverty expert Brenda Boardman'sAchieving Zero offers a devastatingly simpleset of policies that, she says, could make allbuildings in the UK zero carbon by 205012.

Here are just a few of them: Introduce energystandards for existing buildings, and then raisethem over time. Require all homes and busi-nesses to have an energy rating. Get buildingcontrol officers to act as low energy "mentors" onconstruction projects. Develop low carbon zonesin each local authority to tackle clusters of fuelpoor households. Phase out grants and replacethem with subsidies to make energy efficiency loansmore affordable. Reduce taxes on energy effi-cient goods, and on energy efficient properties.Introduce scrappage schemes for old appliances.

Boardman also says it’s essential to her planthat energy efficient properties become worthmore than energy inefficient ones.

Ireland has already taken a step towards thisby making it mandatory to display a property'senergy rating anywhere it is advertised for saleor rent in an admirably strict interpretation ofa requirement in an EU directive.*

Meanwhile, research by the consultancy Copen-hagen Economics, commissioned by Reno-vate Europe, identifies ways to smash someof the main barriers holding back retrofit13.

First, allow landlords and tenants to split the gainsfrom energy efficiency projects — right now,the 'split incentive' means that landlords mustpay to upgrade rented properties but don't �

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Political posturing or meaningful action? David Cameron on a climate “research” trip to Norwaywhen in opposition; (below, second & third from left) Irish enterprise minister Richard Bruton & en-ergy minister Pat Rabbitte spin a green jobs message at the International Energy Research Centrelaunch while retrofit jobs are falling; (bottom) US President Barack Obama announcing a renewableenergy programme in 2009 (p85, top) Association for the Conservation of Energy director AndrewWarren, (bottom) Passive House Institute director Prof. Wolfgang Feist

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enjoy any of the benefits, so they have littleincentive to invest. (Ed. – The new requirementto advertise energy ratings should help makeenergy efficiency a key factor in the rentalmarket, by exposing would-be renters to eachproperty’s energy rating before they’ve formedan opinion about the property – before they’veeven read the property listing, never mind setfoot across the threshold.)

Second, reform public accounting rules sostate bodies can get financing for retrofit. Atpresent many public bodies must put the fullcost of an upgrade on one year's budget —at a time when public budgets are under se-vere pressure. They are often forbidden fromcounting post-upgrade energy cost savings intheir budgets too.

Third, reduce or remove tax breaks and sub-sidies on fossil fuels, which discourage in-vestment in energy efficiency.

And finally, develop smart risk-sharing pro-grammes like energy performance contract-ing. Banks have little experience calculatingthe risk involved with energy efficient invest-ments, so may be reluctant to lend. Retrofitprojects often demand big up-front invest-ment, which implies big risk. Energy perform-ance contracting, under which a utility aims toensure that energy cost savings pay for theretrofit, helps to manage that risk.

But a bigger culture change is needed too.Despite economic meltdown, governments arestill reluctant to intervene too heavily in theireconomies, and are wedded to austerity overgrowth and investment.

Last October, the United Nations said that break-ing the "vicious cycle" of rising unemployment,austerity, fragile banks and deleveraging de-manded "shifts away from fiscal austerity�to-wards job creation and green growth"14.

But what might this shift look like? Last year,Passive House Institute director Wolfgang Feistproposed an "energy revolution" for Europe.With €400bn of investment Europe could trig-ger €3 trillion of private funding and cut theenergy use of all its post-war buildings by85%. This would create 2.2 million jobs, save530 million tonnes of CO2 and trigger four tril-lion euro in energy cost savings, according tothe institute. But Feist said it's crucial thatsuch a programme only support deep retrofitprojects, otherwise it will just cement poor en-ergy efficiency into the system15.**

Retrofitting fuel poor homes also creates moreeconomic growth than cutting VAT or fuel duty,and creates more jobs than spending on othercapital projects, according to research by Cam-bridge Econometrics and the climate changeconsultancy Verco16.

Of course, you might expect groups like thePassive House Institute and Renovate Eu-rope to push for a massive energy efficiency drive.But the International Energy Agency, hardly abastion of green thinking, offers a similar vi-sion in its latest World Energy Outlook.

The report models what would happen in an'efficient world' scenario, in which all "eco-nomically viable" energy efficiency measures— policies that pay for themselves within areasonable timeframe — are implemented forbuildings, transport, power and industry be-tween now and 2035, and all market barriersto their introduction are removed17.

None of these policies would be particularlyonerous or expensive to implement — theyjust demand political will.

In this scenario, governments bring in toughenergy standards for new buildings — and thoseundergoing renovation — and keep pushingthem upwards. Minimum energy standards andlabelling schemes apply to all energy-usingequipment. There are more, and deeper, retro-fits as governments remove barriers to action.Old industrial equipment is retired early andreplaced by the most efficient technology. Toughfuel economy rules, energy labelling and in-centive drives demand for the most efficientroad vehicles. New efficiency rules for powerstations come into force, and more support isgiven to combined heat and power and tech-nology. Smart electricity grids become thenorm.

All of these ideas pay for themselves within stricttime periods. For buildings, this means 14years for heating measures, and three yearsfor electrical ones.

The IEA modelled the economic consequencesof making their 'efficient world' scenario a re-ality. It admitted this is an exercise filled withuncertainty, but is confident the benefits faroutweigh the costs.

Here's what the IEA says happens in their 'ef-ficient world': Demand for oil peaks by 2020,then declines. Demand for coal falls too, whiledemand for cleaner natural gas rises. Energy-related CO2 emissions peak by 2020 and thenfalls. Universal access to modern energy be-comes easier to achieve, and local air qualityimproves, particularly in India and China. Demandfor energy grows much more slowly. The world'scumulative economic output increases $18trillion dollars up to 2035.

But Adrian Joyce of Renovate Europe sayspolicymakers need to look even further, to theless quantifiable benefits of living in warm,comfortable, properly ventilated homes, tofactors such as indoor air quality, productivity,and even happiness.

"These things count in people's lives, but it'shard to put them on a sheet of paper. They'renot taken into account in what are cost optimalmeasures, and in our view they ought to be,"he says.

The Copenhagen Economics study found thatsavings from lower healthcare costs andgreater worker productivity can account foraround half the economic benefits to societyof retrofit, though it admitted such calculationsare fraught with uncertainty18.

But this points to a new way of thinking aboutthe advantages of energy efficient buildingsthat looks at more than just fuel bills. AdrianJoyce says he's constantly touting the needto consider indirect benefits like health whenevaluating the benefits of retrofit. "It piquesthe interest of people, but I wouldn't say it'sgetting traction yet," he says.

"But I'm beginning to feel we're softening theresistance."

*Ireland’s actions are simply a strict interpretation of Article12 of the Recast Energy Performance of Buildings Directive,which states that the energy performance of a building mustbe included in “advertisements in commercial media.” EveryEU member state was obliged to enact this requirement inlaw by 9 January, with no derogations possible**Passive retrofit projects may also be less likely to cause arebound effect, the phenomenon whereby energy upgradesencourage occupants to use more energy by lowering theirbills. It is usually too expensive for building occupants to ad-equately heat all of a highly energy inefficient building. Oncethat building is upgraded to be moderately efficient, it suddenlybecomes easier and more affordable to heat all of it. But if adeep or passive retrofit is undertaken, there is likely to bemuch less of this "comfort taking" as heating the building anyfurther will not make it more comfortable. Research by the PassiveHouse Institute suggests that for retrofit, the actual energyconsumed is very close to that projected. See the series ofarticles on retrofit & refurbishment at http://passipedia.passiv.de)

1National Energy Retrofit Programme Consultation Document,Department of Communications, Energy & Natural Resources(Ireland), 20102World Energy Outlook 2012, International Energy Agency,p290 & 2913Europe's Buildings Under The Microscope, Buildings PerformanceInstitute Europe, p103 & 1044Final Stage Impact Assessment for the Green Deal and EnergyCompany Obligation, Department of Energy & ClimateChange (UK), p148 & p1665Getting the Measure of Fuel Poverty, John Hills, Centre forAnalysis of Social Exclusion, 20126The Impact on the Fuel Poor of the Reduction in Fuel Poverty Budg-ets in England, Association for the Conservation of Energy, 20127Correspondence with Department of Communications, Energy& Natural Resources8Better Energy Homes statistics, www.seai.ie9Correspondence with SEAI10Rabbitte insists he is a good fit for his department and isexcited about future, Irish Times, 4 January 201311Towards a New National Climate Policy: Interim Report of theNESC Secretariat, National Economic and Social Council,June 2012m p86 & 8712Achieving Zero: Delivering Future Friendly Buildings, Brenda Board-man, Environmental Change Institute, University of Oxford, 201213Multiple Benefits of Investing in Energy Efficient Renovationof Buildings: A Study by Copenhagen Economics, RenovateEurope, 201214World Economic Situation and Prospects 2012, Update asof mid-2012, United Nations15Master plan for the European Energy Revolution, presented at2012 International Passive House Conference. www.passiv.de16Jobs, Growth and Warmer Homes: Evaluating the EconomicStimulus of Investing In Energy Efficiency Measures in FuelPoor Homes. Final Report for Consumer Focus. CambridgeEconometrics & Verco, October 201217World Energy Outlook 2012, International Energy Agency, p3518Multiple Benefits of Investing in Energy Efficient Renovation ofBuildings: A Study by Copenhagen Economics, RenovateEurope, 2012

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Passive buildings are meticulously designedto be warm and comfortable based on their localclimate. But our climate is changing — so howwill passive buildings in the UK and Irelandperform as the world gets warmer?

This is, of course, a complex question — a properanswer requires meticulous research and com-plex modelling by experts in climatology andbuilding physics.

But some architects and energy experts arestarting to think about how low energy buildingswill perform on these islands as temperaturesrise and the climate changes.

First, let's look at how the climate might changeover the coming century. It's important to notethat much of this modelling is quite uncertain.

Met Éireann, the Irish meteorological service,says the Irish climate is likely to get 3C to 4Cwarmer by the end of the century. Most of thewarming will take place in summer and autumn,and in the south east. Autumn and winter willget wetter, but summers will get drier. Aver-age wind speeds are not expected to changemuch in the coming decades, and are expectedto get lighter towards the end of the century.

But the frequency of intense cyclones — whichbring heavy wind and rain —is likely to grow.1

The British Met Office's projections for the UKare somewhat similar: the country will get 2.5to 3C warmer, and up to 10% wetter, thoughsome parts of the south will get drier. Extremerainfall events are expected to become morecommon there too.2

So what does all this mean for buildings, andlow energy buildings specifically?

For a start, warmer temperatures should meanless need for space heating. "The heat demandwill come down for most houses in the country,"says energy consultant Andrew Lundberg ofDublin-based passive house consultancy Pas-sivate, whose masters thesis examined howclimate change will effect passive house per-formance in Ireland.3

Architect John Morehead, whose firm WainMorehead provides ultra-local climate data forbuilding project, modelled the annual heat de-mand of a passive house his firm designed inCarrigaline, Co Cork, under a warming climateup to 2100, and found it would fall from 12.1 to9.3 kWh/m2/yr. "That is based on one partic-

ular dwelling," he stresses. "Every building willrespond differently."

Rising temperatures will lead to big drops incold related illness and death, according tothe UK Government's 2012 Climate Change RiskAssessment, which predicted between 3,900and 24,000 less winter deaths each year bythe 2050s.4

And as temperatures rise, it could also providean opportunity to heat our buildings in greenerways. Lundberg says that lower space heat-ing demand should make it feasible to providemuch of a passive building's heating need fromsolar collectors. But he says this presents chal-lenges too: designing a solar system basedon a building's heat load could result in anoversized array, which means building de-signers will need to think about how to store oruse excess heat in summer. Climate changeshould certainly make it possible to downsizeheating systems, though.

But increasing temperatures could also meanoverheating. The UK climate change assess-ment projected deaths from overheating to in-crease by the 2050s, though not as much asthe reduction in cold-related deaths. �

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The coming decades are expected to bring higher average temperatures, more extreme weather events –and possibly more cold snaps. But how are passive house buildings geared to adapt to a changing climate?


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Andrew Lundberg's research found that Irishpassive buildings should cope okay with over-heating through extra shading and passiveventilation. But he thinks that even now, over-heating is an unrecognised issue for passivebuildings in Ireland.

"Overheating is an issue in some passive housesin Ireland and I think it's going to raise its headsoon," he says. "Certainly of the passive housesthat have been built, some are suffering fromoverheating. It's something that the industryneeds to focus on."

Overheating is deemed to occur if the tempera-ture inside goes above 25C more than 10%of the time, according to the Passive HousePlanning Package, the software used to de-sign passive houses.

"In reality that threshold may be too high formany people who aren’t used to those condi-tions in their homes," Lundberg says. He addsthat the summer bypass function on heat re-covery ventilation systems, which brings infresh air without boosting its temperature,often can't exchange enough air to keep in-door temperatures cool in summer (thoughmany people will address this by simply open-ing windows).

"In any well designed passive building, con-trolling overheating is readily achievable throughsimple measures, however it cannot be ig-nored at the design stage," he says — es-sentially the building designer must have astrategy to deal with overheating that will suitoccupants now and in the future, whether it'sthrough shading, ventilation or both.

Too much glazing is the big cause of over-heating in passive buildings, he says.

"Designers can make the mistake of over-glaz-ing the south façade as a means of achievingtarget annual heat demand figures, withoutrealising the detrimental effect this may behaving on summer comfort levels."

This can lead the client to spend more on glaz-ing, shading and ventilation than they're savingin energy costs from the solar gain throughthe windows. "Less south-facing glazing mightbe advantageous," Lundberg says.

West and east facing glazing can also be abig issue, he adds, because the low angle ofthe sun from the east and west makes it moredifficult to control with external shading.

"The simplest way to deal with this may be bynot putting in certain windows at all. A carefulbalance must be struck between the aesthetic,client wishes, daylighting requirements, energydemand and comfort factors. We can’t affordto completely sacrifice any one in favour ofthe other.”

But Lundberg expects overheating to be lessof a problem in passive buildings anyway. "Awell insulated airtight building will generallytake longer to respond to changes [in the out-side environment] than a poorly insulatedbuilding."

How a building responds to changes in out-side temperature and solar gain depends notjust on U-Values — the rate of heat loss througha material — but on the thermal capacity anddensity of construction materials.

"Two completely different wall constructionswith the same U-values can have significantlydifferent decrement delay values," he says.Decrement delay refers to the time it takes forthe peak temperature outside to becomepeak temperature inside.

Some materials slow down this type of solargain more than others. For example masonryconstruction, or choosing insulation such aswoodfibre or cellulose over lighter syntheticmaterials, can offer longer decrement delay.

This isn't generally considered to be of muchimportance in the UK and Ireland, but that maychange as temperatures rise, Lundberg says,and warrants further study.

He also points out that U-values only describe"steady state" heat losses, and that we reallyneed to be analysing a building's performancedynamically using data specific to its location."This is the direction we are heading in, but wearen't there yet."

Designing passive buildings in hot climatesdoes require some changes in strategy though,such as building in more thermal mass, using lesssouth-facing glass, and adding external shad-ing devices to control solar gain in summer.

But Ireland isn't going to turn into the Saharajust yet, and Lundberg's research has found thatduring this century, putting blinds on south-facing windows and introducing a proper sum-mer ventilation strategy should be enough to limitoverheating in passive buildings without theneed for mechanical cooling.

And besides, global warming could also leadto periods of colder weather in winter. The UKMet Office says that greater melting of arcticsea in summer could alter atmospheric circu-lation patterns, creating high pressure over thearctic and low pressure over mid-latitudes, whichtend to bring colder, more easterly winds — par-ticularly in winter. But the Met Office stresses thatother factors are at play too, and the role of seaice in producing cold conditions is still underinvestigation.

Clearly projecting how our climate will changeis a tough task — but regardless, it appears thatairtight, super-insulated buildings are generallybetter protected from the outdoor environment,regardless of whether it's hot or cold out.

And what about rain? Though the projectionsare uncertain, the UK and Ireland — particu-larly in autumn and winter, and particularly intheir mid and northern regions — are likely toexperience more rain. What does this meanfor buildings?

"I'm a bit concerned that people are preoccu-pied with thermal issues, but they're takingtheir eye off the ball with moisture ingress is-sues," says John Morehead.

Rainscreens on external walls are one strat-egy for protecting buildings in areas of highprecipitation. And Morehead typically designsbuildings with deep roof overhangs, a simplebut potentially crucial feature in a wet climate."The overhangs are very important to protectbuildings, particularly because of heavy rain, andparticularly in their vulnerable areas," he says.

He says extremely robust detailing is neededfor external insulation systems — common on

passive buildings and low energy retrofits —in wetter climates. Otherwise wind-driven raingets into joints, into the building fabric, and candestroy the insulation.

He points out an unexpected issue too — thatduring floods, insulation that's too buoyant canrise and lift the slab, so less buoyant varietiesof insulation are needed for the ground floor inflood prone areas.*

He also says that if severe cold snaps were tobecome more common, it would require build-ing designers to think carefully about choos-ing very porous building materials in highlyinsulated buildings — water getting into thefabric would have no opportunity to dry out incold weather, particularly on shaded sites,and the heavy insulation would prevent theheat inside from warming the external wall.

He also says that passive buildings will havean inherent advantage in extreme wind events."The airtightness of a passive house will befar more robust in these situations," he says.

The risks climate change poses to buildingsand infrastructure are likely to outweigh the ben-efits, according to the UK's climate change riskassessment. While heat demand and cold-re-lated deaths will decrease, energy demand forcooling will go up, the risk of heat-related ill-ness and death will increase, the urban heatisland will get worse, water shortages will be-come more common in summer, and flood riskwill shoot up.

Perhaps the changing climate could convincemore householders to meet more of theirneeds on-site. Rising temperatures are expectedto cause electricity transmission losses, andthe increased risk of intense cyclones could meanmore electricity outages, so the self-sufficientcombination of a passive house with on-siteelectricity generation could start to appeal.Equally, the prospect of water shortages in sum-mer could strengthen the case for rainwaterharvesting and storage.

One thing that may need to change is the cul-ture of how we use our homes and offices. An-drew Lundberg reckons there isn't enough ofa culture of "building management" in Ireland.We're not used to closing our blinds before weleave for work to prevent overheating, or pro-gramming thermostats. Residents must takemore responsibility for managing their inter-nal environment, he says.

"My feeling is that the Irish spent so long beingused to just turning the heat on," he says. Thesame could also be said for the UK, where build-ing standards and climate are very similar. "That'sgenerally a cultural issue that we need to dealwith,” he says.

*Engineer Conor Coburn of Construct pointed this out to JohnMorehead on a recent project of his in which a new slab was

being installed in a building in a floodplain

1Ireland in a Warmer World, Met Éireann, 20082Climate: Observations, projections and impacts, United Kingdom.Met Office Hadley Centre, 20113Parametric analysis of the potential effects of climate changeon the performance of a house designed to Passivhaus standardsin Ireland, MSc thesis, Andrew Lundberg, University of Ulster,2009. Available at scanhome.ie4Summary of the Key Findings of the UK Climate ChangeRisk Assessment 2012

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airtightness The degree of air leakage or air infiltration abuilding has. Making a building airtight essentially meanseliminating draughts within buildings, and should not beconfused with windtightness. Both address the sealing ofa building – the internal envelope in the case of airtightness,and the external envelope in the case of windtightness.

Airtightness is typically measured in two units: air changesper hour (ACH) or n50 and air permeability (m3/hr/m2) or q50.

blower-door test This is used to work out a building'sairtightness. A fan mounted to an external door is used topressurise or depressurise the interior of the building, forc-ing air in or out through any gaps or cracks. The building'sairtightness is determined by measuring the force neededto maintain a certain pressure difference (typically 50 pas-cals) between the inside and outside of the house.

BREEAM This is the Building Research Establishment (BRE)Environmental Assessment Method, a UK system used toassess the environmental impact of non-domestic buildings.It considers a range of criteria including energy consumption,water, materials, waste, transport, ecology, pollution and health.It has five levels: pass, good, very good, excellent and out-standing. And fail of course.

Building Energy Rating (BER) The Irish government’srating system used to measure the energy efficiency ofbuildings. BERs range from a ‘G’ for poor efficiency to an ‘A1’for best efficiency, and are expressed in kilowatt hours ofprimary energy use per square metre per annum (kWh/m2/yr).They don’t count all energy use though – only space heatingand cooling, hot water, lighting, and any related pumps andfans. Not to be confused with Building Emissions Rating.

Building Emissions Rating (BER)The British government’ssystem for rating the carbon emissions of a building’s en-ergy use for heating, hot water, cooling and lighting. Forregulatory compliance purposes in the UK the BER score– measured in kg C02/m2/yr – must be below the maximumpermitted Target Emissions Rating (TER).

The Code for Sustainable Homes The BRE’s environ-mental assessment tool for dwellings. As with BREEAM,buildings are assessed on their overall environmental per-formance, resulting in six levels of scoring.

coefficient of performance (COP) This measures theenergy efficiency of certain heating and cooling appliances,such as heat pumps. COP is the ratio of useful energy out-put (heating or cooling) to the amount of energy put in, soa heat pump with a COP of 4 to 1 puts out four times as muchenergy as it uses. The higher the COP, the more efficient thedevice. See also the seasonal performance factor (SPF).

cold bridging See 'thermal bridging'

Dwelling Energy Assement Procedure (Deap) Asoftware programme used to calculate the Building EnergyRating (BERs) of buildings, and to demonstrate compli-ance with energy efficiency targets for new homes underpart L of the building regulations.

embodied energy Energy required to extract, manufactureprocess, transport, and install a product.

greywater Wastewater from baths, sinks, dishwashers,washing machines etc - essentially all a house’s wastewaterexcept that from toilets and macerators/food grinders.

heat recovery ventilation (HRV) A technology thatventilates a building while also recovering heat from ex-

tracted air. HRV systems typically extract warm, damp airfrom ‘wet’ rooms like kitchens and bathrooms and use it toheat cool, fresh incoming air, which is then usually piped toliving spaces such as living rooms and bedrooms. Also re-ferred to as mechanical ventilation with heat recovery(MVHR).

life cycle assessment An examination of a material orproduct’s impact (typically on the environment, but also onpeople/society) throughout its life cycle, from the extrac-tion of raw materials through to its disposal or recycling.

n50 – See airtightness

passive house / passivhaus Passive house is a rigor-ous ultra-low energy building standard. Developed in Ger-many in the early 1990s, the standard has led to the designof buildings that are so energy efficient they don’t requireconventional heating systems.

Passive House Planning Package (PHPP) A softwareprogramme developed by the Passive House Institutethat’s used to design and test buildings aiming to meet thepassive house standard.

Photovoltaic (PV) A technology that uses energy fromthe sun to produce electricity

Primary energy This refers to energy use at source priorto conversion into useful forms, which is referred to as de-livered energy or final energy. The gap between primaryenergy and delivered energy varies enormously for differ-ent energy types. In Ireland, SEAI data shows that the pri-mary energy factor for grid electricity has dropped from 2.7to 2.42 in recent years.

This means that every kilowatt used at the light switch, forinstance, requires 2.42 kWh of primary energy, due to gen-eration and transmission losses. Building Energy Ratingsare assessed in terms of primary energy, as is compliancewith Irish Part L. Note that SEAI’s primary energy data onlytakes into account energy used in Ireland, meaning thatimported fuels may have artificially low primary energy figures.

q50 – See airtightness

seasonal performance factor (SPF) The ratio of use-ful heat energy output from a heat pump to the electricalenergy input (including compressor, circulation pumps andelectrical immersion, if present) averaged over an entireheating season. See also COP

thermal bridging A thermal bridge occurs when heat orcold transfers across an external surface of a building. Thiscan cause heat to escape from the building or cold to enter.Thermal bridging occurs when a thermally conductive ma-terial (in other words, a material with low resistance to heatflow) can penetrate or bypass the insulation layer. For ex-ample, insulation is often placed between timber joists inroofs, however the joists themselves may conduct heatand reduce the effectiveness of the insulation by acting asa thermal bridge along which heat can be transferred outand lost. Thermal bridging can greatly reduce the effec-tiveness of insulation and cause interstitial condensation,so it’s crucial to minimise thermal bridges during the de-sign of a new build or refurbishment.

U-value The U-value of a material is the rate of heat lossthrough that material. The lower the U-value of a material,the less heat can pass through it and the better it is at in-sulating. U-values are measured in watts per metresquared kelvin (W/m2K).

Perplexed by all this talk of U-values, blower-door tests and embodied energy?Our sustainable building glossary will help you get to grips with the key terminology.These entries will be added to an online glossary on www.passivehouseplus.ie,which will continue to grow in detail as each new issue comes out.

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