WIXLIB

1.3 FORMAL ARCHITECTURE5Figure 1.2e Bay windows are used tocapture as much light as possible in a mild butvery overcast climate such as that found inEureka, California.Figure 1.2f In cold climates, compactness,thick wooden walls, and a severe limit onwindow area were the traditional ways tostay warm. In very cold climates, the fireplacewas located either on the inside of the exterior wall or in the center of the building. Thelog cabin was introduced to America by earlySwedish settlers.In mild but very overcast climates,like the Pacific Northwest, buildingsopen up to capture all the daylightpossible. In this kind of climate, theuse of bay windows is quite common(Fig. 1.2e).In a predominantly cold climate,we again see a very different kindof architecture. In such a climate,the emphasis is on heat retention.Buildings, like the local animals, tendto be very compact to minimize thesurface-area-to-volume ratio. Windowsare few because they are weak pointsin the thermal envelope. Since thethermal resistance of the walls is veryimportant, wood rather than stone isusually used (Fig. 1.2f). Because hotair rises, ceilings are kept very low—often below 7 ft (2.2 m). Trees andlandforms are used to protect againstthe cold winter winds. In spite of thedesire for views and daylight, windowsare often sacrificed for the overpowering need to conserve heat.Despite the name, temperate climates are not mild. Instead, they areusually cold in the winter and hot inthe summer. Consequently, temperateclimates are difficult to design for.1.3 FORMAL ARCHITECTUREThroughout history, most masterbuilders and architects have includedenvironmental controls in theirdesigns, just as their unschooledneighbors creating indigenous buildings did. After all, the Greek portico issimply a feature to protect against therain and sun (Fig. 1.3a). The perennial popularity of classical architecture is based on not only aestheticbut also practical grounds. There ishardly a better way to shade windows,walls, and porches than with large

6HEATING, COOLING, AND LIGHTING AS FORM-GIVERS IN ARCHITECTUREoverhangs supported by columns(Fig. 1.3b).The Roman basilicas consisted oflarge high-ceilinged spaces that werevery comfortable is hot climates duringthe summer. Clerestory windows wereused to bring daylight into these central spaces. Both the trussed roof andgroin-vaulted basilicas became prototypes for Christian churches (Fig. 1.3c).One of the Gothic builders’ maingoals was to maximize the windowarea for a large, fire-resistant hall. Bymeans of the inspired structural system of groin vaulting, they were able toFigure 1.3b The classical revival style was especially popular in theSouth because it was suitable for hot climates.Figure 1.3a The classical portico has its functionalroots in the sun- and rain-protected entrance of theearly Greek megaron. Maison Carrée, Nîmes, France.Figure 1.3c Roman basilicas and theChristian churches based on them usedclerestory windows to light the large interiorspaces. The Thermae of Diocletian, Rome(A.D. 302), was converted by Michelangelointo the church of Santa Maria degli Angeli.(Photograph by Clark Lundell.)

1.3 FORMAL ARCHITECTUREsend an abundance of daylight throughstained glass windows (Fig. 1.3d).The need for heating, cooling, andlighting had also affected the work ofthe twentieth-century masters such asFrank Lloyd Wright. The Marin CountyCivic Center emphasizes the importance of shading and daylighting. Togive most offices access to daylight, thebuilding consists of linear elementsseparated by a glass-covered atrium(Fig. 1.3e). The outside windows areshaded from the direct sun by anarcade-like overhang (Fig. 1.3f). Sincethe arches are not structural, Wrightshows them hanging from the building.Modern architecture prided itselfon its foundation of logic. “Form follows function” was seen as muchmore sensible than “form followssome arbitrary historical style.” However, “function” was usually interpretedas referring to structure or buildingcirculation. Rarely did it refer to lowenergy usage, which was seen as aminor issue at best and usually was notconsidered at all. Although that beliefwas never logical, it is clearly wrongtoday since energy consumption is thenumber-one issue facing the earth.Like Frank Lloyd Wright, LeCorbusier also felt strongly that thebuilding itself should be effective inheating, cooling, and lighting. Heincluded thermal comfort and energyas functions in his interpretation of“form follows function.” His development of the brise-soleil (sunshades)will be discussed in some detail later. Afeature found in a number of his buildings is the parasol roof, an umbrellalike structure covering the wholebuilding. A good example of this concept is the Maison de l’Homme, whichLe Corbusier designed in glass andpainted steel (Fig. 1.3g).Today, with no predominant styleguiding architects, they occasionallyuse a mild form of revivalism. Thebuildings in Figure 1.3h use the classical portico for shading. Such historical adaptations can be more climateresponsive than the “internationalstyle,” which typically ignores thelocal climate. Buildings in cold climates can continue to benefit fromFigure 1.3d Daylight gained a mystical quality asit passed through the large stained glass windowsof the Gothic cathedral made possible by groinvaulting. (Photograph by Clark Lundell.)7Figure 1.3e In the linear central atrium of theMarin County Civic Center, Frank Lloyd Wrightused white surfaces to reflect light down to thelower levels. The offices facing the atrium haveall-glass walls.Figure 1.3f The exterior windows of the Marin County Civic Center are protected from directsun by an arcade-like exterior corridor.

8HEATING, COOLING, AND LIGHTING AS FORM-GIVERS IN ARCHITECTUREFigure 1.3g The Maison de l’Homme inZurich, Switzerland, demonstrates the concept of the parasol roof. The building is nowcalled Centre Le Corbusier. (Photograph byWilliam Gwin.)Figure 1.3h These postmodern buildingspromote the concept of regionalism in thatthey reflect a previous and appropriate styleof the hot and humid Southeast.compactness, and buildings in hotand dry climates still benefit frommassive walls and light exterior surfaces. Looking to the past in one’slocality helps lead to the developmentof new and sustainable regional styles.1.4 THE ARCHITECTURALAPPROACH TOSUSTAINABLE DESIGNThe sustainable design of heating,cooling, and lighting buildings can bemore easily accomplished by understanding the logic of the three-tierapproach to sustainable design (Fig.1.4a). The first tier consists of all ofthe decisions that are made in designing any building. When the designerconsistently thinks of minimizingenergy consumption as these decisions are made, the building itself canaccomplish about 60 percent of theheating, cooling, and lighting.The second tier involves the useof natural energies through suchmethods as passive heating, passivecooling, and daylighting systems.The proper decisions at this pointcan reduce the energy consumption another 20 percent or so. Thus,the strategies in tiers one and two,both purely architectural, can reducethe energy consumption of buildings up to 80 percent. Tier threeconsists of designing the mechanical and electrical equipment to be asefficient as possible. That effort canreduce energy consumption another5 percent or so. Thus, only 15 percent as much energy is needed as ina conventional building. That smallamount of energy can be derivedfrom renewable sources both on- andoff-site. Table 1.4A shows some of thedesign topics that are typical at eachof the three tiers.

1.4 THE ARCHITECTURAL APPROACH TO SUSTAINABLE DESIGN9Figure 1.4a The three-tier approach to the sustainability design of heating, cooling, and lighting is shown. Tiers one and two are the domain ofthe architect, and proper design decisions at these two levels can reduce the energy consumption of buildings as much as 80 percent. All itemswith an asterisk are part of solar-responsive design. This image can be downloaded in color for free and used as a poster. It is available atwww.heliodons.org.Table 1.4A The Three-Tier Design ApproachHeatingTier 1Basic BuildingDesignTier 2Natural Energiesand PassiveTechniquesTier 3Mechanical andElectrical EquipmentCoolingConservationHeat avoidance1. Surface-tovolume ratio2. Insulation3. Infiltration1. Shading2. Exterior colors3. Insulation4. MassPassive solar1. Direct gain2. Trombe wall3. SunspaceHeating equipment1. Furnace2. Boiler3. Ducts/Pipes4. FuelsPassive cooling1. Evaporativecooling2. Night-flushcooling3. Comfortventilation4. Cool towersCooling equipment1. Refrigerationmachine2. Ducts3. Geo-exchangeLightingDaylight1. Windows2. Glazing type3. Interior finishesDaylighting1. Skylights2. Clerestories3. Light shelvesElectric light1. Lamps2. Fixtures3. Location offixturesThe heating, cooling, and lightingdesign of buildings always involvesall three tiers, whether consciouslyconsidered or not. Unfortunately, inthe recent past minimal demandswere placed on the building itself toaffect the indoor environment. It wasassumed that it was primarily theengineers at the third tier who wereresponsible for the environmentalcontrol of the building. Thus, architects sometimes designed buildingsthat were at odds with their environment. For example, buildings withlarge glazed areas were designed forvery hot or very cold climates. Theengineers were then forced to designgiant, energy-guzzling heating andcooling plants to maintain thermalcomfort. Ironically, these mostly glassbuildings had their electric lights on

10HEATING, COOLING, AND LIGHTING AS FORM-GIVERS IN ARCHITECTUREduring the day, when daylight wasabundant, because they were notdesigned to gather quality daylighting. As this shows, a building’s energyconsumption for heating, cooling, andlighting is mainly determined by thearchitect at the conceptual design stage.In some climates, it is possibleto reduce the mechanical equipment to zero. For example, AmoryLovins designed his home/officefor the Rocky Mountain Institute inSnowmass, Colorado, where it is verycold in the winter and quite hot in thesummer, to have no heating or cooling system at all. He used the strategiesof tiers one and two to accomplishmost of the heating and cooling, andhe used photovoltaics, active solar,and very occasionally a wood-burningstove for any energy still needed.Table 1.4B Building Form ImplicationsAdvantagesDisadvantagest compactness to minimize surface area, therebyreducing heat gain/losst minimum footprint on landt good for cold climatest cannot be oriented to give most windows theideal orientation of north and southt minimum potential for daylighting, passivesolar, and passive coolingt better for daylighting and natural ventilationthan form It more people have access to views, althoughsome only to the atriumt cannot be oriented to give most windows theideal orientation of north and southt less compact than form I unless atrium iscoveredt larger footprint on land than form It daylighting for whole space if one story anddaylighting for most if two storiest very high quality daylighting since it is mostlytop lightingt very high potential for passive solar heatingthrough south-facing clerestoriest high potential for passive cooling through:t roof vents for natural and forced ventilationt solar chimneyst direct evaporative cooling from rooft no vertical circulation needed if one storyand little vertical circulation if two storiest very large footprint on landt very large surface-area-to-volume ratiot all windows cannot face the ideal orientationof north and south, but clerestories cant if site permits, all or most windows can face theideal orientation of north and southt very high potential for daylightingt high potential for cross ventilationt very high potential for passive solar heatingt larger surface to volume ratio than either formI or IIt if the site requires the long facades to face eastand west, the building will perform poorly;cooling loads will be very high due to all ormost windows facing east or west; qualitydaylighting will also be poort can fit on sites that may not work for form IVt good potential for daylighting especially for thewindows facing north and southt very good potential for cross ventilationt only some windows can face the ideal orientation of north and southt many windows will be facing the problematicorientations of east and westI.II.III.IV.V.

1.5 DYNAMIC VERSUS STATIC BUILDINGS11Figure 1.4b The ideal building form is greatly influenced by the local climate. The building form can minimize heat loss or gain, affect maximumdaylighting, and maximize natural ventilation.When it is consciously recognizedthat each of these tiers is an integralpart of the heating, cooling, andlighting design process, buildings areimproved in several ways: they canbe less expensive because of reducedmechanical equipment and energyneeds; they are usually also morecomfortable because the mechanical equipment does not have to fightsuch giant thermal loads; and theyare often more interesting becausesome of the money that is normallyspent on the mechanical equipmentis spent instead on the architecturalelements. Unlike hidden mechanicalequipment, features such as shadingdevices are a very visible part of theexterior aesthetic—thus, the nameof this chapter is “Heating, Cooling,and Lighting as Form-Givers inArchitecture.”Table 1.4B outlines the advantages and disadvantages of the mainmassing schemes. Figure 1.4b illustrates how massing relates to climate in traditional building. Theappearance of a building is alsoimpacted by surface treatments suchas shading devices, balconies, andgreen walls, which further impact theheating, cooling, and lighting of abuilding.1.5 DYNAMIC VERSUSSTATIC BUILDINGSIs it logical that a static system canrespond to a dynamic problem? Abuilding experiences a very dynamicenvironment: cold in the winter,hot in the summer, sunny one day,cloudy the next, sunshine from theeast in the morning and west in theafternoon, and the angle of sunrayschanging minute by minute and dayby day. Nevertheless, most buildingsare static except for the mechanicaland electrical equipment. Would itnot make more sense for the building itself to change in response to theenvironment? The change can occurcontinuously over a day as, for example, a movable shading device thatextends when it is sunny and retractswhen it is cloudy. Alternatively, thechange could be on an annual basis,whereby a shading device is extendedfor the summer and retracted for thewinter, much like a deciduous tree.The dynamic aspect can be modest,as in movable shading devices, or itcan be dramatic, as when the wholebuilding rotates to track the sun(Figs. 9.15b to 9.15d). Since dynamicbuildings are more energy efficientthan static ones, it is likely that allfuture buildings will have dynamicfacades. A major objection has beenthe difficulty of maintaining movable systems exposed to the weather.However, the present reliability ofcars shows that movable systems canbe made that need few if any repairsover long periods of time. With gooddesign and materials, exposed building systems have become extremelyreliable even with exposure to saltwater and ice in the winter. Perhapsthe modern airplane is an even betterexample of a reliable movable systemthan the automobile. Since no oneshape of wing is ideal for all stages offlight, modern passenger jets changethe shape of their wings as conditionschange (Fig. 1.5). If planes can dothis flying at hundreds of miles perhour in all weather conditions, certainly a building on the ground moving zero miles per hour can also haveextremely reliable dynamic facades.Not only will dynamic buildings perform much better than staticbuildings, but they will also providean exciting aesthetic, the aestheticof change. Numerous examples ofdynamic buildings are includedthroughout the book, but most willbe found in the chapters on shading,passive cooling, and daylighting.

12HEATING, COOLING, AND LIGHTING AS FORM-GIVERS IN ARCHITECTUREthey will be illuminated with daylightmost of the day. Thus, from an energystandpoint resilience is just anotherargument for sustainable design.Cruising1.7 BIOPHILIC DESIGNTake-offLandingBraking on runway1.6 RESILIENT DESIGNWe should design buildings not onlyto sustain the planet but also to sustain its occupants during an emergency. For example, houses on stiltshad a better chance to survive thestorm surges of Hurricanes Katrinaand Sandy than the typical housesbuilt close to the ground.We rely on our buildings’ mechanical systems and imported energy supplies to keep us warm in the winter,cool in the summer, and out of thedark all year. Yet, in January 1998, anice storm in eastern Canada left fourmillion people without power forweeks during the height of the winter. Heat waves in the United Statesand Europe are becoming moresevere and frequent. Is it wise to relyon mechanical equipment and uninterrupted energy supplies? There isa growing conviction that buildingsFigure 1.5 Dynamic buildingfacades are often rejected inthe belief that exposed movablesystems are doomed to fail. Thechanging shape of the wings on ajet airliner indicates that movableexterior systems can be completelyreliable even with snow, ice, rain,and winds of several hundredmiles per hour.should be designed for passive survivability, today more commonly calledresilience. Others prefer the word“adaptive” because we must nowdesign buildings that can adapt to achanging climate.For a building to be resilient itmust be able to operate at least for awhile without energy or water inputsfrom the outside, and it must be ableto survive storms and floods. Becausewe heat, cool, and light buildings with energy, this book focusesonly on resilience related to energy.Fortunately, sustainable buildings aremore resilient because they requiremuch less energy to operate throughefficiency, passive design, and possibly on-site energy production.When power or other energy supplies are not available, resilient (i.e.,sustainable) buildings will get onlymoderately cold in the winter andmoderately hot in the summer, andThe biophilia hypothesis states thathuman beings have a need for connection with living things such aspets, wild animals, plants, and viewsof nature. Recent research in neuroscience and endocrinology supportwhat social research and traditionalknowledge have long indicated: experiencing nature has significant benefits. Consequently, bringing natureinto, onto, and around buildings isnot a luxury but is instead importantfor health, productivity, energy conservation, and, crucially, as this bookwill show, aesthetics (Colorplates 27,30, and 34).1.8 COLOR ANDORNAMENTATIONWhite is the greenest color outdoorsas well as indoors. White roofs havehalf the heat gain of black roofs.White walls also reduce heat gain,and in urban canyons they delivermore daylight to lower floors and thestreets. White cities will experiencecooler heat islands than typical cities. Indoors, white ceilings and wallsreflect precious daylight and electriclighting. White is unquestionably themost sustainable color.Polished metal and glass are alsoused as exterior wall finishes, butboth materials perform more poorlythan flat white. All-glass facades arepopular, but without shading devicesor light shelves they have disadvantages besides the most serious ofpoor energy performance. Whateversunlight is not transmitted indoorsor absorbed by the glass is reflectedlike a mirror to adjacent buildingsand the ground below. This reflectedsunlight causes serious glare and overheating where it was not expected,such as on the north facade of neighboring buildings. Flat white walls,

1.9 ENERGY AND ARCHITECTUREon the other hand, reflect some solarradiation back into space and therest becomes a source of quality daylight for other buildings and theground, which is especially important

4 HEATING, COOLING, AND LIGHTING AS FORM-GIVERS IN ARCHITECTURE Figure 1.2b In hot and humid climates, natural ventilation from shaded windows is the key to thermal comfort. This Charleston, South Carolina, house uses covered porches and balconies to shade both windows and walls, as well as to create cool outdoor living spaces.