low cost green building

7/27/2019 Low Cost Green Building

1/8

Low Cost Green Building: Some Design & PlanningConsiderations

Ajay K Gupta

Managing DirectorKamtech Associates Pvt Ltd.,

Jaipur

General Design Strategies Siting, Land Use, and Landscaping Energy Systems Products and Materials

Environment friendly, use of local materials and better energy managementconcepts and low cost. "I'd like to include green features, but the budget just isn'thigh enough." "Green building is just for wealthy clients." All too often we hearthese claims. And, indeed, a lot of elements of environmentally responsible buildingdo cost more - at least in the short term.

We're talking about first-costhere - how much more (if any) it costs to incorporategreen features into a building project. Life-cycle costs are different. Environmentfriendly, use of local materials and better energy management concepts and lowcost t. It would be wonderful if life-cycle costs were considered as a matter ofcourse in building design today - but they are not. Most of us in the buildingprofession are forced to deal almost solely with first-cost in justifying our projects.

To address this issue - and to counter the perception that building green has tocost more this paper addresses various issues and checklist of design strategies,building practices, and material substitutions that will cost no more than - or actuallycost less than - conventional practice. By no means should this list be consideredcomplete in terms of what can be done on a tight budget. With good integration ofall the disciplines on a design team, it is possible to incorporate, within budget,many strategies that taken alone would increase costs.

Some Cautions on a Low-Cost Agenda

As we examine green design strategies and construction practices that reduce (orat least do not increase) construction costs, it is important to point out that limitingoneself to only those strategies that keep first-costs low may not be in the bestlong-term interest of the client. Sure, we can create better buildings (from anenvironmental standpoint) while spending less money, but realize that too strictapolicy on avoiding those strategies that increase first-cost may result in lostopportunities for even more significant savings down the road. Yes, we should payattention to low-cost strategies, but we should also pay attention to some of thehigher first-cost strategies that can significantly reduce life-cycle costs.

As the green design field matures, it becomes ever more clear that integration is

the key to achieving the energy and environmental goals we desire - especially if


2/8

cost is a major driver. Integration is more than using the savings from one changeto pay for another - it's about making changes that allow other changes to happen.A smaller chiller, for example, makes money available to upgrade the envelope, butit also depends on the envelope upgrade to satisfy the building's needs. Whileintegration can keep construction costs down, it usually requires more time to bespent in up-front design.

Low-Cost Green Design and Construction Practices = RESIDENTIAL

= COMMERCIAL

GENERAL DESIGN STRATAGIES

Renovate olderbuildings.

When we renovate older buildings instead ofbuilding new, we generally save significantquantities of materials and energy, thusbenefiting the environment. In addition toreducing project costs, there may also besignificant savings in time and moneyassociated with not needing as extensiveregulatory review and approvals.

Integrate theplanning anddesign process.

Integrated building design can often result infirst-cost savings. This is certainly the casewith energy design (see below), but savingscan also be achieved in other areas ofbuilding design through careful integration.For example, including the general contractorin early discussions with the architect and

engineer may identify ways to streamline theconstruction process. Involving a landscapearchitect early in the site planning processmay reduce the need for (and cost of)plantings by identifying ways to protect what isalready on the site.

Create smallerbuildings.

Smaller, more space-efficient buildings requirefewer resources during construction, disturbless land during sitework, and use less energyduring operation. Depending on the design,

the total cost is generally lower, though thecost per unit area may be higher.

Look foropportunitiescreated byregulatoryhurdles.

Regulatory obstacles often pose significantchallenges to green design, but they can alsoprovide opportunities in some cases. Forexample, if a regulatory body proposes thatyou spend a lot of money to put in a rainharvesting roof pond, that presents anopportunity to do something better - like


3/8

surfaces, rainwater catchment, and infiltrationbasins. The alternatives may well be lessexpensive, more environmentally responsible,and ultimately more palatable to neighbors

and planning officials.

Optimizeorientation.

When feasible, site a building to optimize solarorientation and access prevailing breezes.With houses, locate more of the windows onthe south than other orientations. It costs little,if anything, to reposition windows and modifythe orientation moderately during design.

Minimize east- andwest-facingwindows.

To minimize cooling loads in houses, reducethe area of windows on east and westfacades. By installing fewer windows, costsshould be lower.

Leave floor slabsexposed.

Rather than carpeting a floor slab, leave itexposed. Molds and other biological pollutantswill be avoided, the environmental impacts ofcarpeting will be avoided, and the cost ofcarpet can be avoided. There are manyoptions for attractively finishing concreteslabs, including texturing and pigmenting.Most (not all) of these are less expensive thancarpeting.

Eliminate droppedceilings.

Savings can often be achieved by eliminatingdropped ceilings. Pendent light fixtures,additional painting, special fireproofingmeasures, and exposed ducts will usually berequired, offsetting some of the savings, butother opportunities may open up as well, suchas deeper day lighting penetration and, insome cases, reduced floor-to-floor height(which can reduce overall buildingdimensions).

Avoid structuralover design.

Optimal-value engineering (OVE) andadvanced framing are strategies for reducingmaterial use without compromising structuralperformance. By reducing material use, thesepractices reduce resource use while savingmoney.

Provide openlayout.

Provide an open room layout in buildings tofacilitate distribution of natural day lighting,reduce ducting requirements for conditioned


4/8

space, and reduce material use. Pay attentionto sound control.

Optimize materialuse bystandardizingdimensions.

Anytime we reduce cut-off waste or use lessmaterial because we have optimized buildingdimensions, we save both resources andmoney. In reducing waste we save moneyseveral ways: by buying less material, byreducing on-site labor (for measuring andcutting), and by paying less for solid wastedisposal.

Save water

Save water. There is usually little, if any,additional cost associated with substitutingwater-efficient equipment. Waterless urinals,for example, eliminate the need for watersupply piping.

LAND USE AND LAND SCAPING

Cluster buildings. By clustering buildings and preserving largerareas of open space, we reduce the costs(and environmental impacts) of pavement,sewer lines, utility lines, rain harvestingsystem, and so forth. The open space alsoserves to protect local ecosystems and

biodiversity.

Select sites thatmake use ofexistinginfrastructure orthat requireminimal extensionof infrastructure.

Where roadways, water, sewer, and utilitylines are already in place or require minimalextension, the infrastructure costs ofdevelopment can be significantly reduced -while the environmental impacts ofdevelopment are reduced and more pristine,undeveloped land is preserved.

Design Rain

harvestingresponsibly.

Conventional practice with both residential

and commercial developments is to carry rainwater in underground tank. A better approachis to allow that water to soak into the groundto replenish aquifers and reduce downstreamflooding. Carefully planned infiltration basinsand measures to reduce impermeablesurfaces are generally less costly thanconventional practice of rain roof harvestingand building large detention ponds. Examplesinclude: avoiding contiguous impermeablesurfaces, minimizing roadway width, and

using porous paving materials.


5/8

Minimize pavedarea.

Minimizing the driveway or access road lengthto a building reduces impervious surfaces,helps preserve open space, and reducesresource consumption - all while saving

money. Also keep streets and drivewaysnarrow, and look for ways to reduce parkingarea requirements. The latter might be done incommercial building projects, for example, byconvincing the company to offer employeeincentives to use public transit.

Avoid cut-and-fill. In site planning and grading plans, avoid orminimize cut-and-fill practices that either carrysoil off-site or bring soil onto the site. Restrictcut-and-fill to on-site movement.

Protect existingvegetation.

It may cost a little more to protect existingtrees on a site, but that cost can easily berecouped through having to spend less onplantings following construction. Large treesaround a new house may also significantlyboost the property value. Protection of shadetrees can allow downsizing of air conditioningequipment, because cooling loads can bereduced.

Use nativeplantings.

Indigenous landscaping (prairies, woodlands,desert gardens, etc.) support wildlife andbiodiversity far better than conventional turf.Native landscaping also does not requireirrigation and chemical treatments (fertilizer,herbicides, pesticides, etc.). In most cases, itcosts less to landscape with native vegetationthan to put in lawns, though costs arevariable.

DESIGN ENERGY SYSTEMS

Provide anintegrated energydesign.

By carrying out integrated design, forexample, a tight, well-insulated buildingenvelope with high-performance glazings andshading strategies may enable you tosignificantly downsize - or even eliminate -conventional heating and/or coolingequipment.

Model thebuilding.

During design, model the energy performanceof a building so that mechanical systems canbe optimized.


6/8

Tune glazings toorientation.

There is usually little if any additional cost inspecifying different glazings for differentorientations. In houses, low solar-heat-gain-coefficient (SHGC) glazings should be used

on east and west orientations, for example,while high SHGC glazings make sense onsouth orientations when passive solar and daylighting are being utilized. In commercialbuildings, low SHGC glazings may beappropriate for south-facing glazings as well,because cooling loads can be high even in thewinter, when the sun is low in the south skyand heat gain from the south is significant.

Consider access

floors.

Access flooring offers opportunities for energy

savings, improved indoor air quality, easierreconfiguration of spaces, and - often -reduction of first-cost. Construction costs aremost likely to be reduced if integrated designwith access floors enable savings elsewhere(elimination of dropped ceilings, reduced floor-to-floor height in multi-story buildings, reducedcooling of under floor supply air, fasterconstruction, etc.).

Expand the

comfort envelopeand downsizecoolingequipment.

By providing operable windows for natural

ventilation or ceiling (paddle) fans to increaseair flow in buildings, occupant comfort can beincreased with less cooling than is typicallyrequired. Reliance on such practices canpermit downsizing of mechanical coolingequipment, reducing equipment costs.

Do not run ductsto exterior walls.

Keeping ducts away from exterior walls willimprove energy performance and save money- because less ducting will be required. Goodenergy performance of the building envelope

is necessary for this to succeed.Provide tasklighting.

By minimizing ambient lighting in commercialspaces and providing task lighting, significantenergy savings for lighting and cooling canoften be achieved even while first-costs arereduced.

PRODUCTS & MATERIALS

Use salvaged

materials.

Salvaged materials can often - but not always

-


7/8

materials. Salvaged materials are beneficialenvironmentally because their use savesnatural resources and reduces pressure onlandfills. Examples of salvaged materials we

can use include lumber, millwork, certainplumbing fixtures, and hardware. Make suresalvaged materials are safe (test for leadpaint, asbestos, and other contaminants).Also, don't sacrifice energy efficiency byreusing old windows on exterior walls, anddon't sacrifice water efficiency by reusing oldtoilets, showerheads, or faucet aerators.Finally, be aware that higher labor costs mightbe associated with use of salvaged materials.

Use structuralmaterials as finishmaterials.

Whenever we can use structural buildingmaterials as finish materials, we eliminate abuilding component that is costly both inresources and dollars. Examples includeexposed beams, concrete floor slabs, and tilt-up concrete panels. It may be necessary tospend more on the structural component tosatisfy design and aesthetic objectives (e.g.,pigmenting and texturing concrete), but thosecosts are usually far lower than the costs ofseparate finish materials.

Consider patiosinstead of wooddecks.

For durability, most wood decks are madefrom pressure-treated wood or from rot-resistant types of wood - the best of which arefrom old-growth forests that are in limitedsupply. A lower-cost alternative (in some partsof the country) is to build concrete, stone, orbrick patios. Masonry costs are highly variableand may not always be less expensive thandecks.

Avoid multiple-pane windows. Instead of multiple-pane, true-divided-lightwindows, install windows with large, singlepanes. These generally offer better energyperformance, are more durable, require lessmaintenance, and cost less. Over a certainsize, however, thicker glass requirements willincrease costs.

Avoid garbagedisposals.

Garbage disposals require significantquantities of water for their operation, andthey result in high organic loading of sewage


8/8

is a much better option for organic wastes.When outdoor composting is not an option,consider worm bins.

Salvage usablematerials. With renovations, salvage materials removedfrom an existing building for reuse. Generally,the extra cost of doing this can be recoveredthrough sale of the materials, or, throughadvertising the availability of free materials, itmay be possible to save on labor costs byhaving the salvaged material recipients do thesalvaging. In either case, moderate savings(depending on local tipping fees) can often beachieved through avoided disposal.

Recycleconstructionwaste.

Carry out a comprehensive job-site wasterecycling program. Some construction wastematerials can be sold, thus recovering theinvestment in separation and separatestorage. More significant savings are oftenachieved through avoided land filling expense.In large commercial projects, the savings canbe dramatic.

low cost green building

Documents