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SA Roofing is the only publication in South Africa that is dedicated exclusively to the residential, commercial and industrial roofing and re-roofing industries.

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Page 1: SA Roofing October 2015 | Issue: 74

OCTOBER 2015 ISSUE: 74WWW.TRADEMAX.CO.ZA SA R36 EACH INCL. / R360 PER ANNUM INCL.

Page 2: SA Roofing October 2015 | Issue: 74
Page 3: SA Roofing October 2015 | Issue: 74

OCTOBER 2015 ISSUE: 74

EDITOR’S COMMENTS ..................................................................................................... 2

CONTRIBUTORS ................................................................................................................ 4

STEEL AWARDS 2015 – CORRECTION ...................................................................... 6

ROOF WINDOWS ....................................................................................................... 8-10

TIMBER DEGRADATION ..........................................................................................12-14

THATCH ROOFING .................................................................................................. 16-17

CEILINGS ............................................................................................................................. 18

CONCEALED FIX ROOFING ................................................................................. 20-21

LSFB ................................................................................................................................. 22-23

BITUMEN INSTANT WATERPROOFING ........................................................... 27-28

WATERPROOFING ....................................................................................................30-31

BUTYL TAPE .................................................................................................................33-34

WATERPROOFING ADVERTORIAL .....................................................................36-38

WATERPROOFING ....................................................................................................39-45

CONSTRUCTION REGULATIONS ......................................................................46-47

INDUSTRY EVENT ........................................................................................................... 48

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OCTOBER 2015

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Trademax Publications

SA Roofing Tel: 0861 SA ROOF Tel: 0861 727 663 Fax: 0866 991 346Email: [email protected]

Postnet Suite 241 Private Bag X103 N1 City

7463

PUBLISHER: Billy Perrin

082 266 6976

[email protected]

EDITOR: Celéste Perrin

[email protected]

ASSISTANT EDITOR: Tracy Swain

[email protected]

ADVERTISING: Jacqui Marsh

[email protected]

LAYOUT & DESIGN: Craig Patterson

[email protected]

SUBSCRIPTIONS: Belinda Thwesha

[email protected]

DISCLAIMER The views expressed herein are not necessarily those of Trademax Publications. Although we have done our best to ensure the accuracy of our content, neither Trademax Publications nor SA Roofing magazine will be held liable for any views expressed or information disseminated, in editorial content or advertisements, in this issue.

Page 4: SA Roofing October 2015 | Issue: 74

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As such, we dread droughts and we love rain. And, it’s always raining somewhere! But, although I feel guilty saying this about such a valuable resource, it can cause

us damage and harm, especially when that gentle rainfall becomes a persistent, torrential downpour that results in flooding. As a construction professional, you may want to know the effect that prolonged rain exposure has on structures that are being constructed – especially timber – and in this issue of SA Roofing, the question is very well answered on page 12.

Staying on the topic, as some of our more densely populated provinces prepare for their rainy season, the all-important aspect of waterproofing again receives focus in this issue. We take a first-hand look at some professional waterproofing projects being completed, and we learn from

several waterproofing professionals exactly why this is such an important aspect of roofing. There are few things more bothersome than a leak, often caused by poor design and damage to already installed systems. Read on to hear the experts explain the importance of both waterproofing product selection and the waterproofing contractor, as well as other important considerations one must not overlook to ensure a weathertight structure.

Of course there’s more to read, including a refreshing take on how roof windows add value to a home. Enjoy, and please feel free to share your feedback, comments and questions.

Celéste

H2OMuch can be said about water: A chemical, it’s the most abundant

molecule on our planet. It’s the only substance that can naturally occur in a solid, liquid and gas form. The Celsius temperature scale is based on water’s freezing and boiling point. It really is the essence of life. We appreciate it,

we need it, and we cannot survive without it.

OCTOBER 20152

Page 5: SA Roofing October 2015 | Issue: 74

No other product has this performance! KLIP-TITE - ONLY FROM GRSDeveloped through continuous in-house testing of Klip-Lok 700, it was evident that failures occurred due to defl ection of the pan during high wind loads causing the sheets to disengage. The following improvements were thus developed:

• Transverse stiffeners were introduced in the pan, to achieve a balanced system design.• Transverse stiffeners reduce the defl ection of the pan, increasing the wind uplift resistance.• The ultimate wind-uplift resistance of Klip-Tite exceeds expectations.• Klip-Tite has retained the superb properties normally associated with Klip-Lok 700.• Transverse stiffeners are a fi rst in the South African sheeting market.

Talk to us, The Smart Roof People on 011 898 2900 or visit www.globalroofs.co.za or email [email protected]

GRSGLOBAL ROOFING SOLUTIONS

There is no approved or equivalent

Delivering the Exceptional Exceptional

GRS Klip-Tite

GRS Klip-Tite

0312 GRS Klip-Tite 2015 (A4).indd 1 2015/05/08 11:04 AM

Page 6: SA Roofing October 2015 | Issue: 74

Contributors

Johan Louw is the director and senior consultant of Johan Louw & Associates, specializing in occupational health and safety solutions for training, auditing and consulting. In 1983 Louw qualified as a mechanical engineer from the University of Pretoria. His early career began at Atomic Energy Corporation as an engineer-in-training. He then moved to Du Toit, Lindeque and Van Den Berg, a consulting engineering firm, in the capacity of mechanical design engineer. From there he moved on and joined Armscor as a systems engineer. During this period he furthered his studies at the Loughborough University of Technology in the United Kingdom, where he obtained a Master’s Degree in Ergonomics in 1989. Louw has been involved in establishing numerous occupational health and safety ventures, and has been affiliated with significant role players in establishing a Health and Safety Standard in South Africa.

JOHAN LOUW

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Upcoming EventsRAWI WATERPROOFING & ROOFING EXPO05 NOVEMBER 2015THE RIVER CLUB GOLF & CONFERENCE CENTRE

Call 021 811 0000 or email [email protected]

2015 – SAEEC(10TH SA ENERGY EFFICIENCY CONVENTION) 11 - 12 NOVEMBER 2015 | EMPERORS PALACE, GAUTENG

Visit www.saee.org.za/cabout.aspx for more info

WOODEX FOR AFRICA9 – 11 JUNE 2016GALLAGHER CONVENTION CENTRE, JHB

Visit www.woodexforafrica.com for more info

OCTOBER 20154

Richard Polling serves MRC Group as the group director. He has been involved with the construction industry for more than 20 years, working for and with some of the largest manufacturers and contractors in the UK. His experience includes designing, manufacturing, installing and maintaining structural steel frames, precast concrete structures, metal roofing and cladding systems, and a range of waterproofing systems. As one of the founding directors of MRC Group, he is actively establishing new standards and innovations in the African construction industry, endeavouring to constantly lift the bar in design, workmanship and maintenance, thereby protecting clients’ investments for up to 20 years – most recently with the introduction of the ‘Guardian’ System Warranty.

Jake Alexander Vlug is the marketing and sales manager at Tony Sandell Roof Windows (TSRW), the leading manufacturer of the centre pivot roof window in South Africa. Vlug studied BCom Marketing in Cape Town before starting at TSRW under the tutorship of the company’s managing director, Andrew Whitaker, who has been in the roofing industry for more than 20 years and is a specialist in slate roofing and joinery. TSRW is a proudly South African company that has been in operation for more than 28 years.

Lyndsay Cotton began his career in the construction industry in 1989 as a technical assistant at the City Council of Pretoria. He graduated in 1992 with a BSc (QS) degree and obtained a Diploma in Project Management shortly thereafter. He is the current chairman of and serving on the board of directors for the Institute for Timber Construction (ITC-SA). Cotton has constructed more than 300 residential projects (upmarket complexes and ultra luxury individual residential units) and is well versed in residential construction – especially with regard to roofing. He was part of the team that established LCP Roofing in 2010. The company now boasts, amongst other achievements, the SANS1900 accreditation for monoplaner prefabricated timber roof trusses (nail plated).

RICHARD POLLING

JAKE VLUG

LYNDSAY COTTON

Page 7: SA Roofing October 2015 | Issue: 74

Built over years, perfected with time.

JCP Roofing is a family business that came into existence through JCP STEEL, a company that

has been serving the steel industry with flat steel products for over 22 years, with a reputation for excellent

service, uncompromising quality and impressive lead times.

Expanding our portfolio to supply IBR and corrugated roofing sheets to the same level of service our customers grew accustomed to over the years, has been our vision

and dream. Take the time to call us on 011 814 1898 and we will help you perfect your project

Products: IBR • Corrugated • Polycarbonate Sheeting • Bullnosing/Cranking • Flat Sheets • Screws & Fasteners

Tel: +27 11 814 1898 | Fax: +27 11 814 2166 Email: [email protected] | Web: www.jcproofing.co.za

0369 JCP Ads.fp.indd 1 2015/08/04 4:30 PM

Page 8: SA Roofing October 2015 | Issue: 74

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Correction to Mediclinic – Midstream, Centurion Steelwork Contractor

(2015 Steel Awards Winning Project) Following the feature on page 46 of the September 2015 edition of SA Roofing, which

recognized the Mediclinic - Midstream, Centurion project as a Steel Awards 2015 winner, Uwe Schlüter, Marketing and Business Development Manager with MiTek, made us

aware of an important omission. We are pleased to set the record straight here.

THE OMISSION: The steel fabricator of the project was not attributed to licensed MiTek supplier Hi-Tech Nail Plate.

TO CLARIFY: MiTek provided the MiTek® Ultra-Span®

profiles and connectors, as well as the software for design and detailing. However, as a licensed MiTek roof supplier, Hi-Tech Nail Plate was directly responsible for the successful assembly, on-site erection and overall installation of the project, which took only five months to complete.

HEREWITH THE CORRECTLY REFERENCED PROJECT TEAM:

CLIENT: MediclinicARCHITECT: Graceland Architects

STRUCTURAL ENGINEER: Cibucon Structural EngineersQUANTITY SURVEYOR AND PROJECT MANAGERS: TMS Quantity SurveyorsMAIN CONTRACTOR: Basil ReadLSF ULTRA-SPAN DETAILER, SUPPLY OF PROFILES: Ultra-Span LGS - MiTek Industries South Africa (Pty) LtdSTEELWORK CONTRACTOR: Hi-Tech Nail PlateCLADDING CONTRACTOR: Rainbow Sheeting

SA Roofing thanks MiTek for the clarification and appreciates the opportunity to acknowledge and congratulate Hi-Tech Nail Plate for the important role they played in this stellar project, worthy of the Steel Awards 2015 accolade it received.

REACHING FOR THE STARS SKA AFRICA The Overall Winner of Steel Awards 2015, the SKA Africa Radio Antenna Positioner, is truly a work of genius.

The judges said: “A scientific project of this nature is a special triumph in the use of steel work... it radiates excellence in every aspect of its structure and purpose.”

Spencer Erling, Steel Awards convenor, says that the quality of this year’s awards matched the excellence of previous years and demonstrated what this outstanding industry can achieve when reaching for the stars.

Southern African Institute of Steel ConstructionTel: +27 11 726 6111 E-mail: [email protected] www.saisc.co.za Steel leaves a legacy.

PARTNER SPONSORS

TUBULAR AWARD

SPONSOR

The Association ofSTEEL TUBE AND PIPE MANUFACTURERS

of South AfricaASTPM

PHOTO COMPETITION

SPONSORFACTORY AND WAREHOUSE

SPONSOR

TABLE DECOR SPONSOR

MAIN SPONSOR

LIGHT STEEL FRAME

SPONSOR

METAL CLADDING SPONSOR

SAISC SKA AFRICA 210x145 ad Sept15.indd 1 9/21/15 4:11 PM

Page 9: SA Roofing October 2015 | Issue: 74

creating the advantage

The low mass per m2 (between 2-10kg) of this roofi ng system ensures both savings on the supporting structure as well as on transportation and erection costs whilst also being vermin proof and non-combustible.Large sections of the roof can simply be pre-assembled on the ground and hoisted into position on the walls – making this one of the most viable systems with a large range of applications up to a clear span of 40m.

Supported through a substantial network of licensed truss suppliers, Ultra-Span is equally ideal for all local and export applications where it can be pre-assembled or site assembled.

The non-combustible solution.

LIGHT GAUGE STEEL

MiTek Park,754 16th Road, Randjespark, Ext. 34, Halfway House,1685. Midrand (Head Offi ce) Tel: + 27(0) 11 237 8700Cape Town Tel: 021 905 0244 • Durban Tel: 031 700 6332 • Port Elizabeth Tel: 041 581 7525email: [email protected] • www.mii.com/southafrica

*MiTek Industries South Africa (Pty)Ltd, a division of the worldwide MiTek Group.

Page 10: SA Roofing October 2015 | Issue: 74

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Tony Sandell Roof Windows (TSRW) is a well known name in the industry and renowned as a specialist manufacturer of roof windows and skylights. Since the

company’s inception in 1988, this industry leader with a national reach has fitted more than 40,000 windows.

SA ROOFING: Why specify a roof window?

JAKE VLUG: Architects all over the world consistently specify roof windows because they have so many applications and benefits. The first and most obvious reason to install a roof window is the natural light it allows for. Many houses have cold, dark areas that could be transformed into warm, light areas with the use of the right window. Roof windows can completely change the whole look and feel of a home and increase its value.

Roof windows also provide excellent ventilation and heat control. With a roof window you can reduce the build-up of mildew, and simply by opening it, you can reduce heat build-up and enjoy fresh air. Both natural light and ventilation play a very important role in our well-being. Roof windows are also a pathway to beautiful views. Instead of a boring old ceiling, a roof window through which you can see out, can unlock or enhance a view to that mountain or the sea, really adding value to your property.

SA ROOFING: The past few years seem to have brought about an upswing in the demand for roof windows, domes and skylights, and even loft conversions. Is that the experience at TSRW as well, and if so, what do you attribute the higher market demand to?

JAKE VLUG: Yes. There has always been a demand for quality roof windows in South Africa, but that demand is undeniably growing – and has in fact exploded over the past two to three years. This increase is attributable to a number of different factors:

First, the use of the loft room, or conversion, is rapidly growing as expanding families need more living space. With both property prices and the cost of moving or relocating so high, many families are opting to – literally – just go up. Our windows are perfectly suited to loft rooms, and with a single unit you can simultaneously add light, ventilation, temperature control, fresh air, and a view.

Another factor is the current, ongoing and huge emphasis on green building. New regulations are continually coming into play, all promoting the use of more energy-efficient products and practices.

Rising electricity prices are also forcing people to turn to more long-term, price-efficient solutions to lighting, ventilation and heat control.

Roofing MattersIn this instalment of our series that shares first-hand information from

various experts within the roofing sector, SA Roofing sets its sights on roof windows, learning more from Jake Vlug, Sales and Marketing

Manager at Tony Sandell Roof Windows.

OCTOBER 20158

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JAKE VLUG: Yes. Roof windows and skylights have to adhere to SANS10400-A and SANS10400-XA. Ratings like summer U-values and solar heat gain measurements must be taken into account. A standard glazing specification under SANS10400-XA will be calculated, and this must be followed and met.

SA ROOFING: Who is responsible for the actual design in terms of shape, size and location (facing north/south/east/west) of the window? What are some of the factors that influence the design and eventual placement?

JAKE VLUG: Lighting and ventilation requirements will determine the size of the window. At TSRW, we have many standard sizes that can be specifically chosen to fit the different truss spacings of different profiles. For example, a 700x1210 will fit in a tiled roof since the average spacing is between 660–780mm, whereas a 940x965 will fit in with a sheet roof where your trusses are around 1,000mm.

The placement will depend on the roof structure, dark area, room centres and ceiling depth. It could be decided by the architect and noted in the plans, or by the client. A good installation consultant should also be able to recommend the optimal placement or location.

SA ROOFING: How long does a typical installation take?

JAKE VLUG: The process is surprisingly quick, with very little or no mess. A standard roof window with the flashings, installation and ceiling trims will take, on average, only a few hours, but is all dependent on the type of roof and ceiling work involved. Our teams each install about three per day.

SA ROOFING: Are roof windows suitable to all roofs (slate, sheets, clay tiles, thatch, flat versus low-pitched, etc.), or are there roof types that should rather not be fitted with roof windows?

JAKE VLUG: TSRW can install into any roof profile and any pitch. Each profile will use its own flashing system. For flat roofs and pitched roofs below 17° we will use an upstand flashing system.

Most houses could do with a roof window, and we don’t have a preferred profile in which roof windows work ‘best.’ A point of note, though, is the common characteristic of thatch roofs having a very large eave that shadows the windows below. So, thatched houses are often very well suited to roof windows. Exposed beam ceilings also look great with roof windows and are the most effective.

SA ROOFING: Taking into account exposure to the weather elements, what should one look for in the exterior frames as far as materials and cladding and/or finishing is concerned?

JAKE VLUG: Considering that the South African climate can be harsh with strong winds and extreme heat and cold, the flashings and roof window unit materials are very important.

OCTOBER 2015

Photograph by: David Rogers

Photograph by: David Rogers

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rain and wind will similarly impact on any imperfection, so make sure that your unit is of top quality and tightly sealed. Avoid at all costs any unit with ‘shady’ waterproofing like a substandard ‘pap en lap.’ Instead, spend the extra money and invest in a maintenance-free, long-term option.

TSRW uses flashings and outer cladding in aluminium and yacht-grade stainless steel. Products that use stainless steel as opposed to galvanized metals are recommended, as they won’t rust or corrode. TSRW frames are made from durable Meranti hardwood, but many competitors use pine.

SA ROOFING: Does it matter if the subframe of the window is not made of solid hardwood?

JAKE VLUG: Hardwood is the best material for the frame as pine and other softwoods tend to warp and rot over time. When you have an outer frame with a sash that fits tight for the waterproofing mechanism, and one of the frames has any movement, it is going to impact the whole unit negatively. Aluminium is a good, strong material, but it has poor insulating values. At TSRW we have found the combination of aluminium and Meranti works best in terms of both functionality and aesthetics and far outlives the cheaper pine imports.

SA ROOFING: Does the window glazing matter?

JAKE VLUG: Yes, glazing is very important, and today’s technology offers the marketplace many performance glazing choices. Double glazing units are a standard in the European skylight market, and a fast-growing trend here in South Africa. The concept entails two pieces of glass with a spacer filled with argon gas between them. Double glazing will reduce noise as well as heat gain and loss.

Polyvinyl Butyral (PVB) or laminated glass is the standard we use. It is 6.38mm thick with a slight cool grey tint to reflect some heat. PVB is the film in the middle and it is 90% UV protective, so furniture and carpets won’t fade. We also use Solar Views, S10 silvers and low E. These are also all performance glass.

SA ROOFING: How is waterproofing ensured when a roof window is installed?

JAKE VLUG: Waterproofing is the key component to a good roof window or skylight, but unfortunately also where a lot of people get it wrong. Our windows are waterproofed with a specialized mechanical flashing made from powder-coated aluminium. Each roof profile has its own unique flashing, from flat concrete decks to 45° thatch roofs.

SA ROOFING: Does it happen that a roof window ‘fails’? If so, what would the cause be, typically, and what steps should be taken to prevent such failure?

JAKE VLUG: Unfortunately there are many cheap skylights available out there, using cheap silicone/butyl and Perspex. The silicone or butyl will eventually perish from the sun if it is not covered. Perspex will similarly become brittle, hairline cracks will start to form, and the window will eventually leak.

Cheap waterproofing is not the answer. It may work for a while, but must then be maintained constantly. As long as you install a quality product, you won’t have a problem with your roof window.

SA ROOFING: What factory manufacturing capability is required, or what machinery is used in the manufacture of roof windows?

JAKE VLUG: All TSRW components are made in our own factory in Ottery, just outside of Cape Town. The raw Meranti we receive is cut to size, planed, primed and then varnished or painted. All aluminium received is in coils and everything is locally produced. Our workshop is over 1,000m2 big and stocked with a wide range of roll formers, planers and profiling machines. Our dedicated team, most of whom have been with us for more than 10 years, know their job to perfection.

SA ROOFING: Would you consider the installation of a roof window as affordable or as a high-cost expense?

JAKE VLUG: Roof windows are definitely an affordable option and a great investment in your home. As with most things, you get what you pay for, and can choose from ‘cheap and nasty’ right through to the very top-end products. Ultimately, if you are going to cut a hole in your roof, do it properly.

For more information, visit www.tsrw.co.za or email [email protected].

TSRW roof window to clay or concrete tiles. More technical detailing (for asbestos, thatch, IBR etc.) is available for download at

www.tsrw.co.za, on the Technical Downloads tab.

OCTOBER 201510

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It was only last year that the South African Weather Service reported that Gauteng had received its highest rainfall recorded in 14 years. That unusual occurrence was mirrored

in many other parts of the country over the same period, with some regions suffering extreme damage to property and actual loss of life.

During prolonged periods of inclement weather, timber framers and truss fabricators have to consider the extent to which structures that are in the process of being constructed are being compromised while they face ongoing exposure to the elements, especially rain and floods.

TIMBER IS HYGROSCOPIC

To answer the question, one first has to look at the basic moisture properties of air- or kiln-dried timber and the South African climate in which these structures are erected.

After drying and grading, the moisture content of structural timber will be less than 15%. Timber is naturally hygroscopic, which means it has a tendency to try and reach a state of equilibrium and balance with the moisture content of the environment in which it exists.

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rain exposure on timber structures

Unseasonal and unusually high rainfall is an underlying effect of global warming, and one that cannot be ignored. There are six climate zones

in South Africa, and with summer fast approaching, it’s the rainy season for some. The question is raised: Are structures under construction compromised when exposed to rain for extended periods of time?

Article by: Lyndsay Cotton, General Manager of LCP Roofing and Chairman of the ITC-SA.

OCTOBER 2015

This truss lying on the ground was exposed to rain for almost 10 days.

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Research by retired Professor Tim Rypstra, who was affiliated with the Department of Forest and Wood Science at Stellenbosch University, concluded that over 90% of South Africa's climate is made up of an average 8% moisture content. Furthermore, most modern heating and cooling systems will maintain an average of 8% moisture content in buildings. From this, it can be accepted that a timber structure, whether a completely timber framed building or only the roof trusses, once ‘settled’ into its environment, will migrate to an average moisture content in the region of about 8%.

TIMBER DEGRADATION

Repeated wetting and drying causes timber to degrade, as the timber continuously swells and shrinks. This can broadly be defined within two categories:

1. WEATHERING: This is repeated and irregular movement of moisture into and out of timber, which will cause various deformations, including swelling, raised grain, warping, cupping and splintering.

2. BIOLOGICAL ATTACK: This occurs both on the surface and/or inside the timber element. Excessive moisture is the primary cause of attack by mould, algae and fungi. Attack by wood borers and termites would also fall within this definition.

A building that was well designed and constructed will not foster conditions that support mould growth or fungal attack, as it will stay dry enough to prevent mould spores from becoming active.

THE TRUTH ABOUT MOULD

Mould, which comes from a variety of sources, results from prolonged high-moisture conditions being present. Mould feeds off the starches and sugars on the surface of timber, but does not cause rotting. Mould growth is a superficial occurrence and will not impact the structural durability of timber.

Bad design and poor construction techniques will result in inadequate ventilation and poor circulation, leading to high levels of condensation. This, along with leaking pipes, gaps in flashings, leaking roofs and porous concrete elements are factors that will lead to the growth and long-term establishment of mould.

For mould to grow on timber, the moisture content has to be above 19% for a period of one week or more. It will survive when, by weight, the moisture content of the structural timber is between 20% and 28%.

The fibre saturation point of timber is at approximately 28% (but can vary depending on the species). This is the point at which wood decaying fungi will develop, and this condition will have to exist for more than a week for it to develop and survive.

THESE CONDITIONS MUST BE MET IN ORDER TO PROMOTE FUNGAL GROWTH:

• The moisture content must exceed 20%.• Oxygen: This condition will not occur when timber is below

the water table. • The optimum temperature for fungal activity is between

24°C and 30°C. (Fungal activity is dormant at 0°C and diminishes beyond 30°C.)

• Fungi require a food supply in order to survive, which is derived from the wood cells. Applying an appropriate fungicide will cut off this source of the food supply.

Active mould growth would indicate a continuing moisture problem and must be investigated.

If and as needed, mould growth can be removed from the surface of the wood by applying a weak solution of standard household bleach. The purpose would not be to ‘kill’ the mould, but to remove as much as possible in order to restore the visual effect and aesthetics of the timber.

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Even after long exposure: Pulling out the nail plate – adhesion to timber was so good that the plate teeth broke off.

OCTOBER 2015 13

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PRESERVATION

Timber ages. With ageing and weathering, it releases its colour, which is contained in the tannins, resins and waxes, which are close to the surface of the timber. Although the sealing and preservation of timber is always preferable, the release of these tannins, resins and waxes, especially in timber where these levels are high, could cause a sealant coat to delaminate. The high temperature levels generally prevalent in roof voids could have the same effect, although this effect would be greatly reduced with the majority of the types of structural timber used in South Africa.

The sealing of timbers in roof voids and framed structures is therefore generally unnecessary unless the incidence of wood borer and termite infestation cannot be excluded, in which case the preservation of the timbers would be mandatory.

IMPLICATIONS FOR THE FABRICATOR, FRAMER, BUILDER AND HOMEOWNER

• Ideally, the contractor delivering the trusses or frames to the building site should cover them. However, it is important that the timber be stacked off the ground and adequate ventilation be provided. The timber must not be completely enclosed with heavy tarpaulin.

• The prolonged exposure of timber trusses to a rainy period not exceeding four or five weeks will not have a negative structural effect, especially if the structure is erected and braced according to the design intent.

• Free airflow should be allowed for as long as possible or until the moisture content is below 15%, whereupon ceilings or internal cladding can be installed.

• Surface fungi and discolouration will not have a negative effect on the strength of structural timber, provided the timber is allowed to dry to below 15% as soon as possible.

• The structure should be covered as soon as possible. • Untreated timber structures should not be exposed to

repeated wetting and drying over a period of many months or longer.

• The homeowner must ensure that all flashings and waterproofing systems are regularly maintained, as most manufacturer and applicator guarantees will only be valid if an annual maintenance plan is in place and executed.

• Fabricators and framers must ensure that all documentation and quality control procedures are in place and are available for inspection should it be required.

• Structural timber in South Africa is under strict third-party surveillance through certification by an accredited certification body such as the South African Technical Auditing Services (Pty) Ltd (SATAS).

• Roof truss and framing design and quality are controlled by internal or independent third-party audits initiated by the ITC-SA (Institute for Timber Construction South Africa, incorporating Timber Frame Builders).

FOR MORE INFORMATION, CONTACT LCP ROOFING:

(c) 082 441 5026 | 0861 LCPROOF(e) [email protected](w) www.lcproofing.co.za

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OCTOBER 2015

Even after long exposure: Pulling out the second nail plate – adhesion to timber was so good, a piece of timber broke off when removing the plate.

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FabricatorsSheetersErectors

Tilers

Leaders in Roof Truss Technology

Page 18: SA Roofing October 2015 | Issue: 74

THE PROBLEMSThis roof was designed at an incorrect angle, namely 35°, where the optimum angle for thatch is 45°. In all likelihood, the goal was to create livable space inside the roof – which would

explain the choice of thatch, normally an ideal roof type for achieving this goal. The size of the roof is 43m2 and the length of the fibreglass ridging is 4,5m.

Thatch: Problems with original faulty constructionThe following case study shows complications where re-thatching was

done onto original faulty construction.

Case study provided by TASA (the Thatchers Association of SA), with input by Dawid Pretorius from Con-Thatch. Photographs courtesy of Con-Thatch.

Roof built at 35 degrees. The rafter spacing is between 900mm and 950mm, where the maximum should not exceed 800mm.

The clear span of ridge beams in the apex of the roof is 4m where it should not exceed 3m.

±900mm

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THE CAUSESThe homeowner tried to claim from the insurance company, but the claim was denied. The obvious question is: Who is to blame? In truth, the problem here is more complex than it appears at first glance, and it is impossible to put the blame squarely in one corner.

The problem could have started with the architect’s original design, with the original builder, with the developer who may have wanted to build as cost effectively as possible, or with the thatching contractor who built a roof at an angle below 45°. Furthermore, the thatching contractor who added the second layer was also at fault, but could have been instructed or influenced by the homeowner to just add the second layer if the owner did not want to go through the inconvenience and cost of having the original layer removed.

THE SOLUTIONIn an ideal world, it would have been possible to increase the height of the roof to allow for a 45° angle. Unfortunately that was not possible in this case, since all the gable walls would have had to be raised as well, making it too costly an exercise. A next-best option would be to build the roof at the same angle but ensure that the construction complies with the standard as laid down by the TASA standards and specifications.

In reality, the only true solution is to remove the existing two layers of thatch, as well as the pole construction, and reconstruct the entire roof. The flashing against the gable would also need to be resealed or replaced should it prove to be necessary.

To prevent faulty construction and resulting thatch problems, TASA strongly recommends that only a reputable, experienced thatch contractor be used, to ensure that industry standards are applied and adhered to.

FOR MORE INFORMATION:

Con-Thatch (TASA member)Dawid PretoriusEmail: [email protected]: www.con-thatch.co.za

TASAElzabie MeintjesEmail: [email protected]: www.sa-thatchers.co.za

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Over the next two financial years, the City will install approximately 8,000 ceilings in homes as part of its commitment to enable redress by improving the lives

of more vulnerable residents. The City secured approximately R116-million in funding for the first phase of this large-scale retrofitting initiative, and work is currently under way.

Between 1994 and 2005, the majority of State-subsidized housing units were constructed without insulated ceilings and weatherproofing. This was because the subsidy, which was then provided by the National Government, did not make provision for the installation of ceilings. Having to live without a ceiling has caused much discomfort for residents who have subsequently been affected by the poor thermal performance of the homes alongside condensation, which gives rise to damp conditions and inferior internal air quality.

“It is estimated that in Cape Town alone, there are approximately 40,000 State-subsidized homes that do not have ceilings. The houses are generally too hot in summer and too cold in winter. Besides the physical discomfort experienced by the occupants, there are also negative health implications. Poor indoor air quality can give rise to and exacerbate respiratory illnesses. It cannot be a coincidence that some of the areas that we are targeting with this project have the highest TB infection rate in the country,” said the City’s Mayoral Committee Member for Human Settlements, Councillor Benedicta van Minnen.

The funding sourced from the City’s Separate Operating Account comprises approximately R91,6-million. Additional funding of R25-million has been received from the Development Bank of Southern Africa’s Green Fund.

After 2005, the standard for subsidized housing was improved and the housing subsidy was increased to provide ceilings, weatherproofing, and partitioned bedrooms. “To improve the condition of houses built before 2005, the City has conducted small-scale retrofitting pilot projects in Kuyasa, Khayelitsha and in Mamre. These houses have been fitted with insulated ceilings and weatherproofing. The pilots have been successful and the lessons that we have learned have informed the planning and design framework for the large-scale roll-out of all housing units across the city that were built before 2005.”

Councillor van Minnen reiterated the City’s full support for the programme, calling on partners and beneficiaries to continue to work together and emphasizing that community engagement and buy-in is key.

The project is being rolled out in Eureka (Uitsig), while plans are afoot for the expansion of the project in other areas such as in Kalkfontein, Vrygrond, Lwandle, Wesbank, Phumlani, Chris Nissen Park and Macassar.

City of Cape Town continues with mass

ceiling retrofit The City of Cape Town and its partners have made great progress with the ceiling retrofit programme to improve the living conditions of beneficiaries

who received inadequate State-subsidized housing between 1994 and 2005.

Photograph by Bryan Pinzgauer

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The Newlok mobile mill, which can be transported on site, rolls the steel forms for the profile in continuous lengths of up to 120 metres. Benefits of Newlok include:

• System is suitable for use on extremely low-pitched roofs • Unique profile offers either a snap-together interlock, or a

snap-and-seam locking mechanism for optimum wind stability

• Exceptional hold-down strength in excess of 3kPa on negative wind uplift on the seamed profile

• Interlocking system allows natural thermal expansion and contraction, without unclipping between purlin supports

• Wide purlin supports for economical design• Concealed fasteners provide increased security, as roof

sheets cannot easily be removed from the outside

When seamed, the standing ‘rib’ provides the perfect attachment substrate for above-roof installations such as solar PV panels, HVAC units, piping and more, without violating thermal expansion and contraction of the roof. Top quality clamps, such as the S-5 range, may be attached to the ribs without penetrating the roof sheet, thus preserving metal material warranties as well as installation warranties on water-tightness.

Metal roofing is making a comeback in house design for its environmental credentials (100% recyclable) and practical values, being long wearing, unique and low maintenance, as well as its aesthetic value.

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Newlok rangeSafintra South Africa has just launched the Newlok ‘Standing Seam’ range – a category of profiled metal sheeting where the side laps are

mechanically seamed for extra lockdown onto concealed fastening mechanisms, and part of the broader ‘Concealed Fix’ category.

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SAFINTRA’S RANGE OF ROOFING PRODUCTS INCLUDE:

• Pierced Profiles Widek™, Trimflute™, Fluteline, Classicor Corrugated and Tufdek IBR.

• Concealed fix profiles Saflok 700 for wider sheet coverage, and Saflok 410 with extra lockdown for challenging wind conditions.

• Versatile™ profile, combining the structural benefits of a continuous steel sheet with the aesthetic appeal of a tile.

• Accessories, flashings and closures, Fixtite fasteners and S5 clamps, and Cleardek multi-wall polycarbonate sheet products.

With concealed fix roofing, a concealed fixing device is used to secure the sheet from under the side lap, thus avoiding the need to pierce the sheet to secure it.

Effective Reduction of Temperature within Attic Space

Protects against Radiant Heat and UV Penetration

bubble RADIANT HEAT BARRIER

®

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According to John Barnard, director of the Southern African Light Steel Frame Building Association (SASFA), one of the great advantages of LSFB is the speed of

erection. “Time is money for the fast-food industry, and it was obviously a significant advantage for KFC to be able to open the Mthatha outlet in only three months after commencement of building. Had they chosen a more conventional building method, they would have started earning revenue at least two months later,” he says.

In this particular structure, a raft foundation was cast and the light steel frame wall panels went up in only three days. Then the heavy steel columns and steel lattice to support the 5,000-litre water tank over the refuse area were erected, with the light steel frame roof trusses following. The building was ready to receive the cladding in only six days.

The external walls were made up of 102mm cavity batt insulation in the frame cavity, 11mm OSB board, a vapour permeable membrane, Mentex Mentlath galvanized steel mesh, and 10mm-thick, double-coat SFH Stucco Plaster. This wall with an overall thickness of 133mm has an R-Value of 3.69 and a fire rating of 30 minutes. The design of the insulating layers of the walls reduces the building's energy requirements for heating and cooling, significantly saving the operator monthly running costs.

The internal walls consist of 15mm-thick Firestop gypsum board on both sides of the LSF, with only the joints skimmed. In all the ‘wet areas’ such as bathrooms and kitchen, 9mm-thick fibre cement board was used.

KFC opts for Light Steel Frame Building

Fast-food chain KFC, in recently choosing LSFB (Light Steel Frame Building) for its new outlet in Mthatha, has joined both McDonald’s and Burger King in

recognizing the advantages of this modern building method that enables energy-efficient building, leaves a reduced carbon footprint, and offers a fresh approach

to creating the right environment for a restaurant whilst, at the same time, contributing towards a sustainable environment.

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KFC said that they were pleasantly surprised at the speed of construction and that they were more than satisfied with the quality of the finishes. “This was particularly impressive as the site was very remote and, owing to materials and skilled labour being scarce, construction is very challenging,” a spokesperson said.

KFC was so impressed with the project that they commissioned the contractor, Silverline, to build other KFC outlets. To date, another KFC has been completed in Colesberg, where it took just five weeks for the superstructure, with roof, to be completed – including all external plaster. Building of a third outlet in De Aar has begun.

Charl van Zyl, CEO of Silverline Group, says the fast-food chains are using LSFB because they support sustainable building methods as far as design, energy efficiency and the optimal use of natural light is concerned. In addition, by using LSFB, material wastage can be reduced by up to 30%, transport costs by 80%, and the carbon footprint significantly reduced. “On top of this, the construction period required is significantly less than with traditional building methods, allowing the franchise to be trading that much quicker,” he says.

Barnard says LSFB is definitely much more energy efficient than more traditional construction methods – both with regard to ‘embodied energy’ of the materials and components, as well as ‘operational energy’ relating to heating and cooling of the building over its design life.

“A recent research project carried out by the CSIR indicated that a LSF building will require less than half of the energy needed to heat and cool a masonry residential building to comfortable internal temperatures,” Barnard concludes.

In recently choosing Light Steel Frame Building for its new outlet in Mthatha, KFC has joined both McDonald’s and Burger King in recognizing the advantages of this modern building

method.

OCTOBER 2015

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ENERGY EFFICIENCY LEGISLATION FOR NEW BUILDINGS (NBR-XA)

The National Building Regulation (NBR) was updated in November 2011 to include Part X, which addresses environmental sustainability and Part XA which establishes requirements for energy efficiency in new buildings and renovations (which require plans). The application of this new legislation is good news for the environment and will help you save electricity.

FEEL THE REAL DIFFERENCE WITH INSULATION THAT MEETS THE REQUIREMENTS

Buildings typically account for 40% of all energy consumed in countries and by insulating with Glasswool it is possible to significantly improve the energy efficiency and comfort of buildings. Isover`s insulation can save 100 times the energy consumed and CO2 emitted in their manufacture, transport and disposal. Glasswool is made from a combination of naturally occurring silica sand, fluxing agents and up to 80% recycled glass. Glasswool has Zero Ozone Depleting Potential (ODP) and no CFC`s or HCFC`s are produced in the production process. Glasswool can be compressed by a factor of up to 5 which saves on storage and reduces transport costs.

CEILING INSULATION

A typical un-insulated home loses and gains up to 35% of its energy through the ceiling and this can be dramatically reduced by installing insulation of the correct thickness.

Think Pink Aerolite is Isover’s thermal and acoustic ceiling insulation solution that reduces the amount of energy required to maintain a comfortable living environment, offering a payback in less than 2 years with continued savings thereafter. Isover Insulation 130 is a non-combustible Glasswool blanket that has been specifically developed to meet the Department of Human Settlements ceiling insulation requirements for 40m2 housing developments became effective in April 2014.

Our insulation is environmentally friendly, non-combustible, offers excellent sound absorption properties and is easy to install in your home.

Feel the real difference with Aerolite or Isover Insulation keeping you warm in winter and cool in summer. For more information log onto www.isover.co.za or download our Isover SA app in the app stores.

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Tel: 0860 ISOVER (476837) Fax: 086 673 1088 www.isover.co.za

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ENERGY EFFICIENCY LEGISLATION FOR NEW BUILDINGS (NBR-XA)

The National Building Regulation (NBR) was updated in November 2011 to include Part X, which addresses environmental sustainability and Part XA which establishes requirements for energy efficiency in new buildings and renovations (which require plans). The application of this new legislation is good news for the environment and will help you save electricity.

FEEL THE REAL DIFFERENCE WITH INSULATION THAT MEETS THE REQUIREMENTS

Buildings typically account for 40% of all energy consumed in countries and by insulating with Glasswool it is possible to significantly improve the energy efficiency and comfort of buildings. Isover`s insulation can save 100 times the energy consumed and CO2 emitted in their manufacture, transport and disposal. Glasswool is made from a combination of naturally occurring silica sand, fluxing agents and up to 80% recycled glass. Glasswool has Zero Ozone Depleting Potential (ODP) and no CFC`s or HCFC`s are produced in the production process. Glasswool can be compressed by a factor of up to 5 which saves on storage and reduces transport costs.

CEILING INSULATION

A typical un-insulated home loses and gains up to 35% of its energy through the ceiling and this can be dramatically reduced by installing insulation of the correct thickness.

Think Pink Aerolite is Isover’s thermal and acoustic ceiling insulation solution that reduces the amount of energy required to maintain a comfortable living environment, offering a payback in less than 2 years with continued savings thereafter. Isover Insulation 130 is a non-combustible Glasswool blanket that has been specifically developed to meet the Department of Human Settlements ceiling insulation requirements for 40m2 housing developments became effective in April 2014.

Our insulation is environmentally friendly, non-combustible, offers excellent sound absorption properties and is easy to install in your home.

Feel the real difference with Aerolite or Isover Insulation keeping you warm in winter and cool in summer. For more information log onto www.isover.co.za or download our Isover SA app in the app stores.

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Tel: 0860 ISOVER (476837) Fax: 086 673 1088 www.isover.co.za

IsoverInsulation

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“The remarkable new product offers completely seamless, fast-track application with rapid drying,” says Mapei South Africa’s Product Manager, Paul Nieuwoudt. “It can be over coated with conventional roof coatings and can be applied over existing torch-on membranes without any special primer. Such is the confidence in the product that guarantees of up to 10 years can be given.”

Plastimul 2K Reactive is a two-component emulsion that is applied by airless spray, thereby providing immediate waterproofing to structures below ground, including the outside of foundations and retaining walls, as well as virtually any surface not exposed to UV.

The blended components begin setting immediately to form a partially-hardened membrane that is highly flexible, waterproof, and resistant to leaching. The tough, fully-cured membrane has a high elasticity and crack-bridging capacity. The product is suitable for all types of concrete and cellular concrete surfaces, limestone, pumice, lightweight brick and breeze-block masonry, render and screeds.

At a recent product training seminar, held at the Mapei South Africa headquarters in Bartlett, Johannesburg, waterproofing applicators were extremely impressed with Plastimul 2K Reactive. The two-day seminar included theoretical and practical product training sessions as well as participative demonstrations of the Spanish Gama spray equipment.

Mapei’s bitumen instant waterproofing emulsion has no local equivalent

South Africa is only the third country in the world to introduce Mapei’s innovative bitumen instant waterproofing emulsion, Plastimul 2K Reactive.

The product is another technology innovation from the international Mapei group, renowned for the production of adhesives, sealants and

chemical products for building.

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APPLICATION AND APPLICATORS’ FEEDBACKDuring the seminar, a secondary school in Durban placed a call for help to solve a long-standing problem with its concrete roof. Continual leakage was being experienced through the existing torch-on membrane, which was not coping on a roof cluttered with pipes, vents and skylights. The school wanted a quick solution with minimal disruption to scholars.

Mapei South Africa knew that Plastimul 2K Reactive would be the ideal solution, and appointed approved applicator, Stonehaven Projects, as the contractor for the job. Applying the product at 3kg/m² to the 480m² roof and finishing with two coats of Mapei Aquaflex Roof HR reflective paint to protect the Plastimul 2K Reactive membrane from UV sunlight, the school’s roof refurbishment was completed in just one day.

Over the course of the seminar, Mapei South Africa took the opportunity to present a refresher course on Purtop 400M, the company’s hybrid polyurethane waterproofing membrane, as well as an overview of the Mapelastic range of sealing products. Purtop 400M is a two-component, solvent-free product that is applied by spraying with a high-pressure, bi-mixer type pump to form a hybrid polyurethane membrane. The membrane is suitable for applications like the immediate on-site waterproofing of viaducts and decks on bridges. It has extremely good resistance to alkalis, dilute acids and detergents, combined with an excellent tensile and tear strength. In addition, its rapid set allows for light foot traffic within only 20 minutes.

“Our product training seminar was highly successful,” says Nieuwoudt. “In particular, the unique Plastimul 2K Reactive, which has no equivalent in the local market, attracted strong interest.”

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Golf & Conference Centre

THE ROOFING AND WATERPROOFING INSTITUTE

EXPERIENCE WATERPROOFING live

EXHIBITIONS STANDS:

POLYUREA EXPLOREDTHE FUTURE OF WATERPROOFING UNRAVELLEDLIVE DEMONSTRATIONS AND WORKSHOPS

5 November 201509h00 - 15h00Waterproofing and Roofing event

Non-Members R3000.00RAWI Members R2500.00

ADMISSIONS – DAY PASS:

CALL: EMAIL:

Non-Members R350.00RAWI Members R300.00(Includes morning tea & lunch)

To book your exhibition stand or day pass

021 811 0000

Tel: 021 811 0000 Email: [email protected] www.rawi.co.za

[email protected]

RAWI WATERPROOFING & ROOFING EXPO

UPLIFTING ETHICS & STANDARDS IN THE ROOFING & WATERPROOFING INDUSTRY

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a.b.e. Construction Chemicals, part of the Chryso Southern Africa Group, supplied three products: bituprime, index unigum, and silvakote, for the two-phase waterproofing project carried out by approved a.b.e. applicator, Jaymark. A total of about 5,000m2 of roofing was waterproofed at Power Park in Epping Industrial, Goodwood, outside of Cape Town.

Glenn Bouwer, Branch and Sales Manager for a.b.e. in the Western Cape, says the roofs were first primed with a.b.e. bituprime, a bitumen primer and sealer usually applied prior to treatment with torch-on membranes, or cold or hot-applied bituminous sealants.

"Then a.b.e.'s index unigum was applied in 4mm thickness. This extremely popular a.b.e. product is a bitumen-polymer

reinforced plastomeric waterproofing membrane, reinforced with a rot-proof, non-woven polyester fabric and strengthened fibreglass mat. The membrane is heat-welded and has exceptional dimensional stability.

"The membranes are covered on the upper face with evenly distributed talc, which allows for easy unrolling during application. The lower face is lined with a protective, non-stick, sacrificial polyethylene 'Flamina' film, which is embossed with small squares to assist in the rapid burn-off of the film. When the film burns off, it shows that the correct melting point for a substrate has been reached. The embossing also allows for vapour diffusion in loose-laid or spot-bonded applications," Bouwer explained.

Comprehensive waterproofing system

for Power ParkThree a.b.e. products were used in a recent two-phase assignment

to waterproof an expansive area of roofing at the Power Park building in Cape Town.

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"a.b.e. unigum membranes are extremely durable and have proven themselves as the solution to even the most difficult waterproofing problems in thousands of South African waterproofing projects. This includes flat, sloping and pitched roofs; reinforced and prefab concrete; masonry cement; metal, and also timber decks and terraces."

The final product used in the waterproofing of Power Park was a coat of a.b.e.'s silvakote, bitumen-based aluminium paint. Silvakote is a UV-resistant, highly reflective paint, suitable for metallic, and most bituminous and concrete surfaces.

a.b.e. bituprime being applied as part of the new waterproofing system for the Power Park premises in Cape Town.

From left: The new silvakote on the roof, followed by the recently applied index unigum on the roof above, and then (towards right) new work is shown, with priming taking place and the new torch-on bituprime being applied.

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VERY, VERY VERSATILE Butyl tape comes in many sizes and has a very wide range of uses in the roofing industry as applicable to gutters, ventilation, flashings, skylights, etc. It never hardens or loses its adhesion properties, loves the sun, and protects against the rain. Butyl tape handles the excessive expansion and contraction of galvanized and polycarbonate sheeting with ease.

It is 100% UV protected. It repels insects and is not rodent friendly. In addition, it is highly resistant to mildew and mould. Butyl tape adheres to itself – and if the tape adhesion is broken, it has a high re-bond ability. Moreover, it has excellent anti-vibration properties in addition to great sound-dampening effects.

The many sides of butyl tape

Tried-and-tested butyl tape has many uses, but one of the most relevant roofing applications is sealing the overlaps of existing or old

roofing sheets. Kenneth Atkinson, Managing Director of Butyl Seal (Pty) Ltd., tells us more and takes us through the paces.

SEAL THE OVERLAPS OF ROOFING SHEETS WHEN IT IS BETTER TO SEAL THE LAP JOINT WITH A WIDER PIECE OF BUTYL TAPE THAN TO LIFT THE SHEETS AND SEAL THE JOINT WITH LAP SEAL.

Identify the place where the two joins meet, and make sure they are free of any particles that may interfere with the adhesion of the tape. For example: Old, flaking paint is not a good surface, and the

presence of oil will prevent adhesion.

It is easy to repair a leaking fastener. The butyl tape encloses the entire head and becomes a temporary or permanent fix.

Place the butyl tape over the lap, with even spacing on either side of the lap. Once firmly in place, the butyl tape is ready to be painted with most types of paint. And because it is 100% UV protected,

the butyl tape will last for many years.

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For more information, contact Kenneth Atkinson via phone (011) 462-1840 or e-mail [email protected].

Here’s a great example of how to seal between two sheets of old galvanized sheeting. It couldn’t be easier.

Plugging holes is a breeze when using butyl tape. Painting afterwards enhances the professional look.

OCTOBER 2015

On the cover: LCP Roofing

PROJECT: Completed for a private school – Blue Hills Equestrian Estate, Reddford House School

BUILDING: Early Learning Centre(Photographed by Stacy Priestley for LCP Roofing)

TIMBER USED: SA Pine

CLIENT: Century Property Development

CONTRACTOR: Lexkon

SUBCONTRACTOR: LCP Roofing (Pty) Ltd. Manufacturing and erection of the timber roof trusseswww.lcproofing.co.za

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“The cost of heating and cooling a building is a massive expense. Prior to the introduction of SANS10400 and energy-efficiency regulations, some developers and contractors were installing the cheapest possible roofing and glazing options in order to offer a more attractive selling price for their developments and properties,” Ed Scott-Turner from Aspect Waterproofing, a PWASA member (Professional Waterproofing Association), explains. “Unfortunately that often left uninformed homeowners with a house freezing in winter and scorching in summer, resulting in high costs associated with constant heating, air conditioning, using fans, etc., not to mention the strain it put on the already diminished electricity supply.”

Leonard Scott-Turner, also a PWASA member and owner of Concrete Junction Waterproofing as well as DipSystems Insulation, concurs and adds that the regulations concerning energy efficiency of structures now help to ensure more appropriate power usage by the building owner or homeowner.

SANS AND THE WATERPROOFING PROFESSIONALLeonard further clarifies that the Regulations do not govern waterproofing directly, but pertain specifically to the actual thermal insulation of roof structures based on the R-Value required in each climatic zone within South Africa, as determined by SANS10400 or SANS204 and as calculated by the architect or design engineer. “The synergy between waterproofing and insulation is critical, and we offer a turnkey solution to all clients,” he states.

Because each climatic region experiences different weather patterns, humidity levels and other weather conditions, waterproofing methods are different in certain areas. The experienced waterproofing professional can assist the architect or engineer upfront with an optimal insulation and waterproofing design, customized to the specific contract, which will ensure a successful installation and watertight structure. This applies to the roof, the walls and also under the slab (surface bed).

SANS: Unlocking a new chapter in waterproofing The advent of SANS10400-XA and SANS204 has had far-reaching effects

on the building and construction industry, and very specifically where insulation standards and minimum heat loss and heat gain ratios are

concerned. But the waterproofing sector, too, is an important partner in ensuring compliance. SA Roofing learns how.

102 Rivonia Rd – DIPS Insulation Boards and stone backing.

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Example: In most instances, the architect designing the structure so that it complies with the Regulations will, instead of just indicating that a flat roof be painted, specify that DIPS board (Neopor® Drainage Insulation and Protection Boards) with a stone ballast be used, as part of the submission to satisfy SANS. (Another method of achieving the required heat loss/gains would be by specifying double glazing.) All modern waterproofing systems require maintenance coatings every two to three years if exposed to sunlight.

The use of the DIPS system provides a maintenance-free solution to the horizontal areas, with the maintenance coating only required for the exposed parapet walls and plinths. Using DIPS in the waterproofing application allows for, as the name suggests, drainage insulation and protection, resulting in the required insulation standard being achieved. Subsequently this saves on the Silvercoat – both at installation stage as well as with ongoing maintenance required in respect of the guarantee.

“The waterproofing component of most buildings is normally in the region of 1% and sometimes slightly more or less, but it is most frustrating and irritating when it was not done correctly from the outset, and you then have leaks that inevitably cause damage and have to be taken care of, at a cost,” Ed continues, reiterating again the importance of using an experienced waterproofing contractor who knows what the right application is for the job. “There are new and innovative waterproofing products on the market such as Polyurea Trafficable Waterproofing Systems, which are specialist spray applications with amazing characteristics, installed by qualified companies like Custom Linings. Then there are materials such as the Hydrolock products (Nukote HLT Impregnating Agents), used as concrete slab waterproofing and applied to green concrete or cured concrete. There are also TPO mechanically

fixed type systems, which are slowly becoming more cost efficient in order to rival some of the other traditional waterproofing systems such as torch-on membranes.”

Leonard concurs, pointing out the renewed importance of correctly waterproofing buildings where insulation is now critical and subject to stringent checks. Since the Regulations have been in place, not only industry professionals but also the public has taken note of the importance of achieving the ultimate goal of well insulated and watertight structures – and the need to source specialist and reputable contractors to do so.

SPECIALIZED TRAINING AND ASSISTANCE The qualified architect, engineer or main contractor, or the official building inspector, is responsible for signing off that the structure is compliant with Regulations and that it is watertight. Again, the result will be contingent on selecting a waterproofing company that is qualified to do the work.

Architects, design consultants and engineers undergo specialized training via seminars that address the correct insulation of structures, and they will similarly seek out other professionally qualified partners to collaborate with on their waterproofing requirements. Waterproofing professionals should take advantage of the training, assistance and competence certification that membership to recognized waterproofing bodies provides. For example, through an association membership and all the training it entails, the waterproofing contractor will be able to, via detailed drawings, demonstrate to the architect or engineer right from the start that he can fulfil the requirements.

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L TYPICAL ROOF SLAB DETAIL2 coats Klodec acrylic complete with reinforcing membrane to tops and sides of upstand beams

100mm Uniflash self-adhesive bitumen membraneovercoated with 2 coats Klodec acrylic

Mortar cove

One layer 4mm Polyglass Evolight reoxthene modifiedbituminous torch-on membrane with 100mm wide sidelaps and 150mm wide end laps on screeds to falls toroof slabs including turnups, etc.

One layer PT115 geotextile fabric loose laidon top of insulation board including turningaround edges of perimeter boards

50mm Grey crushed granite stone ballast loose laid on top of filter fabric

100mm DIPS EPS drainage insulation protection board

Screeds to falls

OCTOBER 2015

Main roof - typical perimeter upstand beam detail.

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serve the building, construction, roofing, insulation and waterproofing industries in an over-arching manner through many interconnected standards compliance criteria, such as the Building Industry Bargaining Council, CIDB, the Waterproofing Federation of South Africa, even SARS and entities focused on public liability insurance (extremely important for the builder and the client as they would be held liable if they employ “Bakkie Brigade” contractors who are not compliant to the various statutory bodies as mentioned), etc.

Any waterproofer who wants to be a member of such bodies will have to prove compliance to their specific, individual criteria on a regular basis. Membership to professional entities like PWASA and WARAC (Waterproofing and Roofing Association Cape) will reassure building contractors and other professionals that they are selecting a more established, qualified and specialist waterproofing contractor that will meet that criteria.

CONTINUALLY IMPROVING STANDARDS

When compared to international standards, South Africa’s Regulations compare favourably, Leonard states, and although Europe and the USA are still setting the pace, we are catching up to advancements quickly. Ed agrees, but cautions that enforcement of the Regulations remains a challenge for the industry.

As a parting word of practical advice to fellow industry professionals, Leonard does not recommend the use of any insulation under a roof screed as this is extremely risky. Ed recommends to fellow professional waterproofers that they offer their expertise and assistance in terms of waterproofing, lining and insulation skills to the design team from the outset and before the project goes ahead.

For more information, the authors Ed Scott-Turner and Leonard Scott-Turner can be contacted via e-mail to [email protected] and [email protected] respectively.

Aspect Waterproofing, Concrete Junction Waterproofing, Custom Linings and DipSystems Insulation

are members of PWASA (the Professional Waterproofing Association, South Africa) and embrace its rigorous standards of high-quality waterproofing applications, with the inclusion of thermal insulation, in a ‘green’ and environmentally friendly way.

With operations throughout southern Africa, the grouping’s collective experience of over 250 years is backed by their expert knowledge of proven as well as new, cutting-edge products and applications to advance the waterproofing sector. They offer modern, hard-wearing and sustainable options to consumers as well as trade, and regularly engage with architects, structural and civil engineers, main contractors and other building professionals in finding watertight solutions to waterproofing problems.

Photograph: Horizon Towers, Mozambique.This extensive project entailed waterproofing, joint sealing, trafficable waterproofing to the parking deck, roof gardens waterproofing and drainage, work on the balconies, and insulation. All waterproofing design and installation done by Concrete Junction Waterproofing, Cretecor Concrete Junction Mozambique, Custom Linings, and DipSystems Insulation.

www.concretejunction.co.za

BRANCHES (T) +27 11 672 5455/6 (F) +27 11 672 6137(E) [email protected]

Concrete Junction is a specialist consulting and contracting company with the ability and capacity to design, install and insure high quality professional applications of waterproofing in the Construction, Civil Engineering, Corporate and Mining Industry.

Whether it’s a Stadium, Commercial, Industrial or your dream home, we weather proof them all.

WWe operate in all areas of Southern Africa including Neighbouring Countries

JOHANNESBURGDURBAN CAPE TOWN MAPUTO www.dipsystems.co.za

T: +27 11 472 8051 F: +27 11 672 6137E: [email protected]

DRAINAGE INSULATION & PROTECTIVE SYSTEMS

Drainage Insulation and Protection Board is Manufactured using NEOPOR (Graphite Enhanced EPS) as well as in various thicknesses depending on the Requirements in respect of the Insulation (R) Values in each Climatic Zone.

WESTERN CAPE & EASTERN CAPE

21 YEARS ON AND STILL GOING STRONG

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(021) 460 0453 (041) 360 0094

• Reliable • Quality • Efficient • Service

TEL: 082 894 168417 Prins Street, Brits, 0250PO Box 652, Broederstroom, 0240

www.customlinings.co.za

• Industrial Linings• Spiral Refurbishment• Chemical & Acid Resistant Linings• Sprayed on Waterproofing Systems• Containment Systems• Abrasion Resistant Linings

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It is important that maintenance schedules – and budgets – are fully prepared and implemented. An annual inspection and review of the planned maintenance and budget is not only necessary to identify urgent items, but is crucial to ensure accurate reporting and management of all maintenance items.

Source: Checklist © Frederik Nel, Curasure (Pty) Ltd.

As a precautionary measure, before the start of the rainy season in your region, it is strongly recommended that a comprehensive site inspection be performed so that

action items can be listed and taken care of to prevent damage to the building and property.

The following checklist, courtesy of Curasure (Pty) Ltd., serves as a reference to ensure that critical parts of the building envelope are not overlooked:

Your checklist for the rainy season

The importance of preventative as well as ongoing building maintenance, supported by good life cycle costing and practical, workable maintenance

plans, is regularly emphasized – and for good reason.

1ROOFS (PITCHED, TILED, FLAT OR WATERPROOFED)

Depending on the style of roof design and waterproofing, the items will vary. Make sure that cracked tiles, ridge cappings and general flashing detail are in good order. For flat roofs, ensure that counter-flashing and outlets are fully waterproof and well maintained.

2 GUTTERS AND DOWNPIPES Repair and maintain gutters and downpipes; ensure good flow of water.

3 PARAPETS Make sure that parapet walls are waterproofed and sealed correctly.

4 SKYLIGHTS AND FITTINGS All roof skylights and accompanying fittings must be sealed and secured.

5BALCONIES, TILED AREAS, WATERPROOFED AREAS

Ensure that tiled and waterproofed areas are correctly waterproofed. Outlets must also be waterproofed correctly, be open and sufficient.

6 WINDOWS AND DOORS Inspect and reinstate failed sealing of doors and windows. (Install weather strips if required). Include windowsills in the inspection.

7 WOODWORK Inspect and maintain all woodwork prior to the expected rainy season.

8 GENERAL BRICK AND PLASTERED SURFACES

Repair all cracks and defects. Continue to perform routine checks and maintenance as required.

9 RISING/NEGATIVE DAMPThis problem is not reserved for coastal regions alone, and numerous complexes all over the country exhibit damp-related failures. Unfortunately this problem is not easily taken care of and requires in-depth investigation and specification to resolve.

10 CARPORTS Ensure that shade-netting on carports is tightened and in good serviceable condition.

11 BUDGETSIf not already in place, then be sure to set up a maintenance budget and ensure that sufficient funds are allocated for preventative and interim maintenance prior to rainy seasons or major projects.

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In the Xhosa language, Indawo means place, and the company’s motto, ‘Maintaining your place is what we do,’ couldn’t have been more apt in the case of Century on Lake,

where Indawo’s skills were needed to rid the complex of persistent leaks. To start, Indawo performed a thorough inspection that included checking the full-bore outlets for pipe and drainage problems.

INSPECTION AND OBSERVATION

Initially, the existing waterproofing membrane appeared to be in relatively good condition. However, reported leaking was subsequently identified and confirmed at various points on many of the roofs. It appeared that the leak problems had been exacerbated for some time; as soon as one section got repaired, a new problem manifested itself in another area.

The parapet walls were also found to be compromised, with signs of water damage evident. It became clear that the waterproofing membrane used was not to the required standard. Cracks were visible, especially in the corners.

RECOMMENDATION AND BRIEF

Indawo recommended the complete installation of a new waterproofing system on the roofs of the cottages. The client approved the brief to relay a new waterproofing membrane, according to specifications, on the cottages situated on the lake side of Century on Lake.

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woes at Century on Lake To combat their rainy season, Century on Lake, situated in Century City,

Cape Town, commissioned the waterproofing of flat-roofed cottages that were showing signs of deterioration and leaking. Indawo (Cape)

stepped in and swiftly took care of the problem.

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PROJECT SCOPE

• Move existing stone chips on top of the waterproofing membrane to one side of the flat roof.

• Lift existing waterproofing membrane.• Repair existing screed where needed.• Lay new waterproofing membrane.• Repeat process on other half of the roof.• Sift stone chips before relaying on top of new waterproofing membrane.• Full-bore outlets to be fully stripped around the full-bore, to allow for ease

of application of the new waterproofing membrane and to prevent ponding by bitumen membrane build-up.

• Flood test.

PROJECT CHALLENGES

One of the primary challenges facing waterproofers in Cape Town during winter (the typical rainy season) is the unpredictable weather pattern. Winter rainfall, especially, creates uncertainty when undertaking waterproofing projects. A close watch on the weather is required to identify breaks during which the waterproofing membrane can be installed successfully.

High winds, too, provide unpleasant working conditions – not only for the site staff, but also for residents and visitors to the complex. Giving full consideration to owners, tenants and visitors, Indawo staff took great care to reduce the spread of dust while they were sifting and moving the stone chips. Excess sand was also carefully removed from the roofs to avoid inconveniencing owners and tenants. The project team was led by Indawo production manager Roel van der Heijden and included the contracts manager, Martin Geldenhuys.

OUTCOME

The choice of the new waterproofing was critical for the success of the installation, and Indawo provided an optimal solution that also took into account the client’s available budget:

A torch-on elastoplatomeric polymer bitumen membrane (compound in distilled bitumen, modified with high molecular weight polymer, reinforced with non-woven spun-bound polyester fabric and glass stabilized) was applied in a multi-layered waterproofing system.

For more information, visit www.indawo.biz.

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Long-term waterproofing system failure is a common occurrence, often due to insufficient product knowledge or incorrect application. Most products in the

marketplace leave the manufacturing plant fit for purpose, but how it is applied is the key factor for long-term success. When choosing a contractor or installer qualified to install the waterproofing product, it is essential to check whether they are associated with the industry trade associations. Also important is whether the length of term of the product warranty they offer is matched by their workmanship, including areas such as the perimeter details. Incorrect or shoddy application will leave you holding the bill – maybe not this year or the next, but eventually incorrect applications always catch up with the building owner.

STATE OF THE ROOFConsideration must be given to both the type of roof the waterproofing system is being applied to as well as its current condition before application. If it’s rusted or already has a failed waterproofing system in place, precautionary measures need to be taken prior to application to clean the roof to ensure the success of the new waterproofing system. Trying to apply a new waterproofing system to an existing failed waterproofing system could end in disaster.

THE PROBLEM AREAS Metal Roof: Old, rusty or leaky metal roofs most often have leaks occurring at the flashing details (vents, fasteners, valley gutters, ridge caps, skylights, etc.) and at the roof end and side lap details, due to previous incorrect installation or lack of maintenance. Daily thermal movement and harsh weather conditions can, over time, cause screws and fasteners to loosen, thus creating opportunity for water ingress.

Asbestos Roof: While asbestos is water resistant, over time the material becomes porous and weak, leaving it susceptible to water ingress through damaged sheets and the opening-up of the side and end laps. As the roof sheeting becomes older, access to the roof becomes more difficult and more damage to the sheeting can occur.

Flat Roof: Water ponding is a common problem experienced with most flat roofing systems. Internal drainage failure or long-term thermal expansion damage will allow excess water to form ponds, which can increase in size over time. Most waterproofing systems are not guaranteed under long-term water ponding. As a result, the weight of the water puts a tremendous strain on the structure that can cause structural damage and possible structural failure.

Waterproofing pitfalls With more and more waterproofing systems being added to the marketplace every year, selecting the right waterproofing system can be a confusing and tedious task.

With this vast array of waterproofing solutions, the uninformed end user could quite easily make the mistake of choosing cost over a quality product and qualified installer.

While cost is certainly a factor to consider, an incorrectly installed waterproofing system is likely to fail – resulting in a leaky mess and unnecessary, costly repairs.

Article by Richard Polling, National Business Development Director - MRC Group South AfricaPhotographs courtesy of MRC Group.

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OPTIONS‘Torch-On’ Bitumen Membranes: Ideal for sustaining harsh weather conditions and offering complete water damage protection that is impact- and tear resistant. Torch-on coatings provide excellent elasticity, ensuring all usual movement is well accommodated, restricting any unnecessary structural damage and costly long-term repairs.

Liquid Applied Waterproofing Coating: Providing a seamless monolithic waterproof coating to almost any roof system and associated gutters, these systems can be applied with brushes, rollers or spray systems, depending on the application type and size. This method of coating means that vast areas can be applied extremely quickly and with exceptional drying times to provide a weather-tight solution.

‘Cool Roof’ Liquid Applied Waterproofing: In most cases, these have all the benefits of a liquid applied waterproofing system – but with an added advantage of ‘cool roof’ technology, which either reflects or dissipates the sun's rays. This reduces the temperature of the existing roof system, resulting in significant reduction in thermal movement and internal air temperature. For example, a metal roof sheet can achieve temperatures of up to 100°C in the summer, but with the application of a ‘cool roof’ waterproofing system this temperature can be reduced to below 50°C.

Single Ply Roof Membranes: Roofing membranes have been used for decades as a quick-to-install waterproofing solution that can negate the issue of application onto existing failed waterproofing systems by using the option of mechanically fixing the single ply roofing membrane back to the structure. Additional insulation can be installed between the existing roof and the new membrane roof system to upgrade and enhance the thermal performance of the roof.

WATERPROOFING SYSTEM SPECIFYING REQUIREMENTS: KNOW YOUR FACTS To assist with product selection, here are some common terms to look out for:

• Light Reflective Value (LRV): Indicates the level of light reflected and absorbed by an object or surface when exposed to light. Any surface with an LRV of less than 50% will absorb more light, resulting in darker appearing colours and a hot surface area. Surfaces with an LVR greater than 50% will reflect more visible light, creating a much cooler, temperature-stable environment.

• Emissivity Value: Measures how effectively a body’s surface radiates energy that has been absorbed by the body. A perfect emitter would have an emissivity value of 1 and would freely radiate absorbed energy back into the environment. Surfaces with low emissivity hold on to absorbed energy and do not radiate it freely. Emissivity plays an important role in how a material performs in a given environment.

• Solar Reflective Value (SRI): Using a scale of 0 – 100, the SRI of a surface is calculated for a given surface. SRI combines the values of solar reflectance and emissivity to give an indication of how hot a surface will become when exposed to sunlight. It is normally preferable to have a high SRI (cooler surface) as this reduces thermal movement (expansion and contraction) of a roof, degradation of polymers by heat (materials last longer), and heat transfer into the building. For particularly hot or cool surfaces, the SRI can sometimes reflect below 0 or even above 100.

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Some products offer great LRV, but the emissivity of the material may be low – often reaching extremely high temperatures of around 80°C. These temperatures increase thermal movement, resulting in preventable damage. For best results, source products that offer a combination of impressive LRV, Emissivity and Solar Reflectance, for a well-rounded waterproofing solution that will extend the life of the roof, reduce energy needs, and ensure no further leaks for many years to come.

• Material Elasticity Daily thermal movement is unavoidable, even if significantly reduced with the use of a cool roof coating. It’s imperative to select a product with flexibility and elastic properties, to ensure it’s able to easily withstand daily expansion and contraction without being susceptible to tears or damage. A flexible waterproofing system will also bridge cracks that develop over time and prevent future leaks from occurring.

CLEANING OR PRIMING As waterproofing systems are used quite substantially in the refurbishment marketplace, it is essential to understand what the new waterproofing systems is being applied to. New galvanized roof sheeting generally comes with rolling oil from the manufacturing process. Moreover, the moisture content of concrete structures and screeds, as well as existing failed waterproofing systems will all have a long-term impact on the ability of the new waterproofing system to remain adhered.

In some cases, thorough correct cleaning of the existing roof is the preferred route. In other cases, application of a keying primer can be the best way. Each needs to be considered on a project-by-project basis.

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APPLICATION SPECIFYING REQUIREMENTS The current industry standard is to provide a long-term product guarantee with a short-term application or workmanship warranty and no maintenance element, leaving the building owner holding the bill should failure occur.

Any specifier looking for a long-term, successful waterproofing application should select a knowledgeable and experienced

installer willing to offer a warranty to cover design, material, workmanship and maintenance of equal length of terms. Regular maintenance of the waterproofing roof system and its associated gutters is key to ensuring its success. If not maintained correctly, the system is sure to fail at some point.

KEYS TO SUCCESS• Clear understanding of what the waterproofing system is

being applied to• Correct specification of the waterproofing system• Experienced and controlled application• Continued maintenance for the life of the warranty

For more information, contact Richard Polling at MRC Group on cellular (0)79 340 2318, e-mail him at [email protected] or visit www.mrc-group.co.za.

MRC Group offers the Guardian System Warranty, an innovative single-source, transferable building envelope warranty that covers up to 20 years of the building envelope’s life, providing coverage not only for materials and workmanship, but also design and maintenance.

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HEAD OFFICE: (011) 397 4441WEB: www.rooftruss.co.za

THE COMPLETE SYSTEM SUPPLIER TO THE PREFABRICATED TIMBER TRUSS INDUSTRYThe first nail plate company in SA to have received the prestigious SABS 9001 quality management award, which ensures that only the highest level of services and products are provided.

CALL 0861 727 663 TO BOOK YOUR

CLASSIFIED ADVERT

OCTOBER 2015 45

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POINT OF CLARIFICATION NO. 1One of the most important starting points when reading legislation is to fully understand the scope of application thereof. Regulation 2: Scope of Application, of the Construction Regulations, clearly stipulates that “these Regulations are applicable to all persons involved in construction work.”

POINT OF CLARIFICATION NO. 2It is of paramount importance to fully understand the definition of “construction work,” as the scope of application is confined thereto. The Construction Regulations define construction work as any work in connection with:

a.) the construction, erection, alteration, renovation, repair, demolition or dismantling of or addition to a building or any similar structure, or

b.) the construction, erection, maintenance, demolition or dismantling of any bridge, dam, canal, road, railway, runway, sewer or water reticulation system; or the moving of earth, clearing of land, the making of excavation, piling, or any similar civil engineering structure or type of work.

Paragraph (a) of the above definition refers to the following:

• Activities relating to a building or similar structure.

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One can safely argue that Construction Regulations, 2014, is potentially the single most misunderstood and misinterpreted set of Regulations of the Occupational Health and Safety Act, 1993. One has to acknowledge that these Regulations do have quite a number of shortcomings. To understand ‘which structures designers are responsible for in the construction industry,’

one has to gain several levels of understanding.

Article by: Johan Louw, B Ing (Mech), MSc (Ergonomics) – Director, Johan Louw & Associates

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POINT OF CLARIFICATION NO. 3It is important to note that the definition of a “building” is defined in section 1 of the Act, which states that a “building” includes –

a.) Any structure attached to the soil,b.) Any building or such structure or part thereof which is in

the process of being erected, orc.) Any pre-fabricated building or structure not attached to

the soil.

Firstly, one has to consult the dictionary meaning of a building, because of the term ‘includes’ that appears in the definition of a “building,” which means, “a relatively permanent (could therefore also be temporary) construction over a plot of land, having a roof and usually windows (could therefore also not have windows) and often more than one level (could therefore also have one level), used for any of a wide range of activities, such as living, working, entertaining, or manufacturing.”

Secondly, when comparing paragraph (a) to paragraph (b) of the abovementioned definition of “building,” it is without doubt in conflict. It is therefore a definition, which, in terms of paragraphs (a) and (b), has limited value in terms of explaining to the reader what a “building” is, as that would then include virtually anything from a pole and a tree, to chairs and benches bolted to a floor, etc.

POINT OF CLARIFICATION NO. 4Paragraph (b) of the definition of “construction work” refers to the following:

• civil engineering structures or structures falling within the category of civil engineering structures, or

• the moving of earth, clearing of land, the making of an excavation or piling or any type of work falling within the context of the aforementioned types of work.

One has to realize that “the moving of earth, clearing of land, the making of an excavation or piling or any type of work falling within the context of the aforementioned types of work” has to be for the purpose of the following:

• the construction, erection, alteration, renovation, repair, demolition or dismantling of or addition to a building or any similar structure, or

• the construction, erection, maintenance, demolition or dismantling of any bridge, dam, canal, road, railway, runway, sewer or water reticulation system.

In other words, as an example, the digging of graves (which is the making of excavations) to bury the deceased, is most certainly not for construction-related purposes.

POINT OF CLARIFICATION NO. 5One further has to interpret the definition of “structure” as defined in the Construction Regulations, 2014, correctly. A "structure" means:

a.) any building, steel or reinforced concrete structure (not being a building), railway line or siding, bridge, waterworks, reservoir, pipe or pipeline, cable, sewer, sewage works, fixed vessels, road, drainage works, earthworks, dam, wall, mast, tower, tower crane, bulk mixing plant, pylon, surface and underground tanks, earth retaining structure or any structure designed to preserve or alter any natural feature, and any other similar structure,

b.) any falsework, scaffold or other structure designed or used to provide support or means of access during construction work, or

c.) any fixed plant in respect of construction work which includes installation, commissioning, decommissioning or dismantling and where any construction work involves a risk of a person falling.

It is interesting to note that only paragraphs (b) and (c) refer to “construction work,” but not paragraph (a). Not only is paragraph (a) in conflict with paragraphs (b) and (c) but also with Regulation 2: Scope of Application. In other words, a steel structure, e.g. a tank stand, pipe racks, water and gas pipes, etc. referred to in paragraph (a), which are all steel structures but definitely not a “building,” fall under “a structure designed by a designer” referred to in Regulation 6: Duties of Designers. The intention of the legislature with regard to which structures a designer is responsible for in terms of Regulation 6, is only “structures” in relation to “construction work,” as indicated by paragraphs (b) and (c) of the definition of “structures.”

CONCLUSIONFinally one can answer the question of which structures designers are responsible for: Based on the clarity gleaned through the preceding discussion points, it is clear that the intention of the legislature is that only structures which are for the purpose of “construction” work, are the ones that designers have obligations for as stipulated in Regulation 6: Duties of Designers.

For more information, contact Johan Louw with Johan Louw & Associates on 012 998 4102 or visit www.jla-solutions.co.za.

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CALL 0861 727 663 TO BOOK YOUR SPACE IN

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Organized by Acropolis Exhibitions, WoodEX for Africa will be held from 9 to 11 June 2016 at Gallagher Convention Centre in Midrand, South Africa.

Stephan Jooste, CEO of Acropolis Exhibitions, says the event is now reaping the rewards of relationships that have been built and nurtured over the past four years within the international and local timber industry. "We are very excited about WoodEX and about the loyal support from our industry friends and media partners, our repeat exhibitors, and dedicated visitors from throughout Africa. We have listened to all the suggestions received through the years and we are incorporating ideas into next year's event.

"With the XIV World Forestry Congress held in Durban recently it is apt that WoodEX will focus on developing the forestry section of the event next year. We trust that our forestry partners and friends who attended the congress had a successful event and that they will share their forestry expertise, experience and future vision with the rest of the timber industry at next year's WoodEX," says Jooste.

WoodEX for Africa is currently the only expo in Africa focusing exclusively on the timber industry and is the perfect platform for woodworking professionals to connect with specialized dealers, to catch up with the latest timber trends, to secure new business contacts, and to compare deals.

At the conclusion of WoodEX for Africa 2014, the event received valuable input from both its exhibitors and visitors, with exhibitors reporting positive feedback in terms of the quality of visitors, the great networking opportunities, market exposure, and business conducted. Visitors indicated that they were specifically impressed with the outstanding quality of the exhibitors' displays and the professional appearance of the event.

For more information about participating in WoodEX for Africa as an exhibitor or event partner, visit www.woodexforafrica.com or e-mail [email protected].

Exhibition bookings for WoodEX for Africa 2016

filling up fastDemand for exhibition space at WoodEX for Africa 2016 is once again exceeding all expectations, with some of South Africa’s biggest and most

respected timber industry businesses already committed to showcasing their products and services at the event. More than 70 percent of exhibition

space has already been pre-booked.

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BOOKNOW!

EXPLORENEW BUSINESS

OPPORTUNITIESAT AFRICA’S ONLY TIMBER MACHINERY, TOOLING, MATERIALS & FITTINGS EXHIBITION

9-11JUNE2016

Gallagher Convention Centre | Midrand | South [email protected] | +27 (0) 21 856 4334

www.woodexforafrica.com

Furniture & Kitchen production | Forestry & Sawmilling | Wood Materials, Machinery & Veneers Tools, Loggers & mobile Saws | Timber Construction and supply | Industry Surface & Treatment Technologies

Many more Timber related products, machinery and services.

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CORROSHIELD® Fasteners are coated with our unique coating that provides our carbon steel fasteners

with exceptional corrosion resistance capabilities. These specially coated fasteners are specifically developed

for outdoor environments where they are exposed to the contamination of natural and industrial atmospheres.

CORROSHIELD® Fasteners are coated with our proprietary CORROSHIELD® HD & CS coating for superior

outdoor application, especially in highly corrosive coastal and industrial regions. This propriety coating formula

consists mainly of Zinc and Aluminium to combat deterioration of steel surfaces. It provides far more

advantages in comparison to conventional electroplating, dip spin coating and even mechanical plating.

Corrosion resistance performance of fasteners used in building and construction is crucial because

they provide integrity and security to the other system components. Corrosion of ferrous fasteners can lead to

failure of building systems as a result of their premature deterioration.

Tests conducted on CORROSHIELD® Fasteners by internationally accredited laboratories have found that we comply with corrosion resistance

requirements of Australian Standards AS3566 (2002), Class 3 and Class 4. Further corrosion test methods in accordance to ASTM D6294 (2003) were also

applied to assure further compliance of our fasteners performance under various environmental categories (SS-EN-ISO 12944-2) .

CORROSHIELD SOUTH AFRICA16 Van Tonder Avenue Malanshof Randburg Gauteng 2194E : [email protected] : www.corroshield.co.za