intro to green building
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  By Alexis Karolides Part 1: Resource Efficiency T oday it is commonly assumedthat the built environment willdegrade the natural one, butthis belief is not based on historical evi-dence. For most of earth’s history, struc-tures built for shelter have typicallyenhanced biodiversity and benefited thesurrounding community. Beaver dams, forinstance, create eddies where wetlandsform, supporting a vast array of diverselife. Why should an office building be anydifferent?“Green building” is a way of enhancingthe environment. It benefits humans, thecommunity, the environment, and abuilder’s bottom line. It is about tailoringa building and its site to the to local cli-mate, site conditions, culture and com-munity, in order to reduce resource con-sumption while enhancing quality of life. There is no singular “look” for a greenbuilding. While natural and resource effi-cient features can be highlighted in abuilding, they can also be invisible withinany architectural design.Likewise, a green building is not anassemblage of “environmental” compo-nents or a piecemeal modification of analready-designed, standard building. These approaches not only add to thebuilding’s cost, but also produce marginalresource savings at best. True green build-ing takes a holistic approach to program-ming, planning, designing, and construct-ing (or renovating) buildings and sites. Itinvolves connecting often-interlinkedissues such as site and climate, buildingorientation and form, lighting and ther-mal comfort, materials, etc., and optimiz-ing all these aspects in concert. In orderto capture the multiple benefits of syner-gistic design, the “whole system” designprocess must occur early in the building’sconception and involve interdisciplinaryteamwork. In the conventional, lineardevelopment process, key people areoften left out of decision-making orbrought in too late to make a worthwhilecontribution. Early and complete collabo-ration, however, can reduce or eliminateboth capital and operating costs, while atthe same time meeting environmentaland social goals.It is precisely the integrated approachdescribed above and the multiple benefitsthereby achieved that allow many greenbuildings to cost no more than standardbuildings, even though some of theircomponents may cost more. Green designelements may each serve several func-tions and might allow other building com-ponents to be downsized. For example,better windows and insulation can resultin smaller heating systems; photovoltaicpanels can double as shade for parking orcan replace a building’s spandrel glazing.Buildings use 40 percent of total (including 60 percent of electrici-ty) and 16 percent of total U.S. water;they produce 40 percent of the waste inlandfills. Natural Capitalism  documentshow radical improvements in resourceefficiency are readily possible—today’soff-the-shelf technologies can make exist-ing buildings three to four times moreresource-efficient and new buildings tentimes more resource-efficient.Reducing energy use in buildings savesresources and money while reducing pol-lution and CO 2 in the atmosphere. It alsoleverages even greater savings at powerplants. For the average 33-percent-effi-cient coal-fired power plant, saving a unitof electricity in a building saves threeunits of fuel at the power plant.As RMI’s Amory Lovins has often said,“It’s cheaper to save fuel than to burn it.”But full financial benefits will only berealized by using the integrated approachdescribed above (high performance win-dows will increase initial costs unless thedesigner takes proper credit for smallerheating and/or cooling loads and equip-ment). Just as important as what goesinto a green building is what can be leftout. Green building design eliminateswaste and redundancy wherever possible.One of the key ways of reducing resourceconsumption and cost is to evaluate firstwhether a new building needs to be built.Renovating an existing building can savemoney, time, and resources, while oftenenabling a company (or a family, if it is aresidential building) to be located in a About the Author RMI’s Alexis Karolides, a former Richter Fellow, holds a Masters of Architecture degree from Rice University.A registered archi- tect with six years’ commercial experience, she was previ- ously the sustainability manager for the architectural firm Sussman Tisdale Gayle.This three-part series on the basics of green building is adapted from the forth- coming book Green Building: Project Planning & Cost Estimating , coauthored by Karolides. It is scheduled for publication in late October by R.S. Means Co., Inc., and is available from the publisher at 1-800-448-8182 or at,in the website bookstore under “New Releases.”  An Introduction to Green Building   7 RMI Solutions  Fall 2002  part of town with existing infrastructureand public transportation, enhancing con-venience and reducing sprawl. If a newbuilding is required, it should be sizedonly as large as it really needs to be.Smaller buildings require fewer materials,less land, and less operational energy. Ourcultural assumption is that we should buy(or lease) as much square footage as wecan afford. Yet the average new housesize has steadily increased over the pastfew decades while families have gottensmaller. Smaller houses and commercialbuildings allow the budget to be spent onquality, not “empty” quantity. Energy . The easiest and least expensiveway of reducing operational costs in abuilding is to lower its energy consump-tion—best done by increasing energy efficiency. There are great energy-cuttingopportunities in simple designs thatrespond to location and climate. MostNorth American buildings should facetheir long side to within 15 degrees of true south (and use proper shading toblock summer sun but not winter sun). This can save up to 30 or 40 percent of the energy consumption of the samebuilding turned 90 degrees.Heat travels in and out of buildings inthree ways: radiation, convection, andconduction, all three of which must beaddressed. Radiation is the transfer of heatfrom a warmer body to a cooler one viainfrared rays. They can be blocked byusing reflective surfaces. Convection is thetransfer of heat by heat-driven circulationof a fluid or gas, such as air. Convectiveheat transfer can be controlled by sealinggaps around windows, doors, electricaloutlets, and other openings in the build-ing. Conduction is the transfer of heatacross an immobile substance. Everymaterial has a specific conductivity (U-value) and resistance (the inverse of theU-value, called the R-value). Metal is agreat conductor, so if high-performancewindows have metal frames, there will bea “thermal break” in the frame (an insulat-ing material inserted to block the heattransfer across the metal).As the above descriptions suggest, one of the best ways to reduce heat loss or gainis by installing the appropriate high-per-formance window for the given climate. The right window can save energy,enhance comfort, allow space-condition-ing systems to be downsized, reduce fad-ing from ultraviolet light, reduce noisefrom outside, reduce condensation, andimprove daylighting.Once the building envelope is designed toreduce heat flow, we can use a number of natural heating and cooling methods todownsize or even eliminate fossil-fuel-based heating and cooling systems. Techniques include daylighting, passivesolar heating, natural ventilation, passivecooling, efficient and right-sized HVACsystems, and utilization of waste heat.Daylighting enhances visual acuity for occu-pants, creates a connection to nature, andincreases productivity and well-being. It alsoreduces operational energy costs as electriclights are turned off or dimmed when day-light is sufficient. This points out the impor-tance of integrating all the technical sys-tems—daylighting, lighting, and space-con-ditioning. It is also important to design sys-tems for varying loads.When energy loads are as small as practi-cal, appropriate renewable energy sourcesshould be evaluated. These include wind,biomass from waste materials, ethanol fromcrop residues, passive heating and cooling,and photovoltaics. An electrically efficientbuilding might be less expensive to buildwith “off-grid” power than to connect tothe grid. Demolition/Construction Practices. With any site development it is impor-tant to protect adjoining agriculturalareas, rivers, and trees, and to be espe-cially vigilant about erosion control.Rather than degrading the surroundingenvironment, development can enhance it.Next, demolition and construction shouldbe carefully planned to reduce or eliminatewaste. Typically, demolition and construc-tion debris account for 15–20 percent of municipal solid waste (and sometimes asmuch as 40 percent), while estimates arethat 90 percent of this “waste” could bereused or recycled. Reusing and recyclingwaste is not only the environmentallyfriendly thing to do, but could save moneyand promote local entrepreneurial activities.It is critical to note that reusing, salvagingand/or recycling materials requires addi-tional up-front planning. The contractormust have staging/storage locations andmust allot additional time for sortingmaterials, finding buyers or recycling cen-ters, and delivering materials to variouslocations if buyers don’t collect them. Third party commissioning. When thebuilding is completed, third party buildingcommissioning—making sure systems areinstalled and running as designed and asefficiently as possible—can save as much as40 percent of a building’s operating costsfor heating, cooling, and ventilation,according to Lawrence Berkeley NationalLaboratory. Ongoing regularly scheduledmaintenance and inspection are also criticalto maintain the performance and efficiencyof the building and its mechanical systems. Recycling. Americans produce an esti-mated 154 million tons of garbage—roughly 1,200 pounds per person—everyyear. At least 50 percent of this trashcould be, but currently isn’t, recycled.Recycling doesn’t stop at the jobsite.  The building should be designed to fosterconvenient recycling of consumer goodsthroughout the life of the building. Thisusually entails easily accessible recyclingbins or chutes, space for extra dumpstersor trash barrels at the loading dock, and a recycling-oriented maintenance plan. Green Building Next issue: Environmental Sensitivity. 8 RMI Solutions  Fall 2002
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