Building materials in eco-energy houses from Iraq and Iran

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Almusaed, A., Almssad, A. (2015)

Building materials in eco-energy houses from Iraq and Iran

Case Studies in Construction Materials, 1: 42-54

https://doi.org/10.1016/j.cscm.2015.02.001

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Case

Study

Building

materials

in

eco-energy

houses

from

Iraq

and

Iran

Amjad

Almusaed

*

,

Asaad

Almssad

b

KarlstadUniversity,Sweden

1. Introduction

Vernacularhabitatsdevelopedtheirindividualitybytappingintonearbyresourcesandexploitingthemtoconfrontthe problemsposedbyalocalenvironment.Ifrainisseasonal,theroofstructuremustalsofunctionefficientlyinthedryseason (Woolley,2006).Whenitiswarm,large,ahighroofspacecontinuumwiththelivingareaispractical.Temperatureextremes callfor thickinsulating walls androofs tomaintaina comfortable internal environment(Almusaed,2004). Themost importantquestionthatneedstobeanswerediswhatistherelationshipbetweentheouterconditionsoftemperature, sunshineandrainandtheinsidethermalcomfort.Fordifferentclimaticsessions,itisnecessarytotakeintoaccountbuilding, area,orientation,colours,etc.Althoughitisquiteacomplicatedmattertotheoreticallysolvetheseproblems,itispossibleto ARTICLE INFO

Articlehistory:

Received17August2014

Receivedinrevisedform24December2014 Accepted5February2015

Availableonline11March2015 Keywords: Environmentalprofiles Ecologicalmaterials Energyefficiency Vernacularhabitat ABSTRACT

BuildersfromtheWesternpartofAsiaaretrainedtomakebuildingsthatcanfulfilcertain required functions while giving full consideration to all sites and environmental conditions.TheresearchcoversthezonebetweenIraqandIran.Thefirstinvestigated regionisthe‘‘MesopotamianMarshes’’orIraqi-IranMarshes,awetlandzonesituatedin southernIraqandpartiallyinsouthwesternIran.Theotherregionisadesertdistrict, whichincludesaprominentpartofthesouthernandwesternpartsofIraqandpartofIran. Thelast isthecentrecityof Basra.Thebuildingmaterialswerethemostimportant buildingelementthataffectedtheconformationofvernacularhabitatsfromthewestern partofAsiaingeneralandtheIraq–Iranareainparticular.Inthisstudy,weneededtofocus ontheeffectsofecologicalandenergy-efficiencyprocessesincreatingvernacularhabitats andtheselectionofoptimalbuildingsystemsandmaterialsinthispartoftheworld,which canbeanessentialpointforsustainableenvironmentalbuildingprocessesinthefuture. Reeds,clay,straw,bricks,andwoodwerethemostpopularbuildingmaterialsusedby buildersfromthisregion.Theimpactofbuildingmaterialontheenvironmentembodies the essential method implicitly significant in this research to effectively determine traditionalbuildingmaterialsintheenvironment,inadditiontocomparativeanalysis. Thispresentsanessentialfactorofouranalysis,inadditiontotheimpactofenvironments onbuildingsystems.Themaintargetofthisstudyistobenefitdesignersandbuilding engineersintheirpursuittofindoptimalandcompetentsolutionssuitableforspecific localmicroclimatesusingtraditionalmethodsinthedesignprocessthataresustainable andecological.

ß2015TheAuthors.PublishedbyElsevierLtd.ThisisanopenaccessarticleundertheCC BYlicense(http://creativecommons.org/licenses/by/4.0/).

*Correspondingauthor.Tel.:+4524252391.

E-mailaddress:a.amjad@archcrea-institute.org(A.Almusaed).

ContentslistsavailableatScienceDirect

Case

Studies

in

Construction

Materials

j o urn a lhom e pa g e : ww w . e l se v i e r. c om / l oca t e / cs cm

http://dx.doi.org/10.1016/j.cscm.2015.02.001

2214-5095/ß2015TheAuthors.PublishedbyElsevierLtd.ThisisanopenaccessarticleundertheCCBYlicense(http://creativecommons.org/licenses/by/ 4.0/).

establishanempiricalrelationshipbetweentheexteriorandinnerenvironmentsforanybuilding.Inthisway,thepractical problemcanbesolved(GinvoniMan,1976).Throughouthistory,thehumanbeinghasstriventoerectsheltersthatfulfil basicneedsrelatingtohissurvival,shelterthatprovidesanenvironmentfavourabletohisphysicalrequirements.Duringhis yearsofefforttoachievethatenvironment,manylocalvariationsindwellingshaveevolved(Wenzel,1996).Accordingtoa UNdocument,thepurposeofthehabituationprocessisnottobuildhousesbuttoovulateacompetenthouse.Inotherwords, thehouseshouldprovidethesecurityoftechnicaladviceandbeinvolvedinacquiringsmallloansandcheapmaterials(Stulz, 1981).Climaticconditionscompelthebuildertofindanefficientsolutiontoservethehumanbeingandthecomfortofhis existence.Buildingmaterialshaveanimportantimpactonthehome’sfunctionsandinhabitants.Environmentalbuilding materialsaddvaluetohumanlifeandreducethenegativeimpactontheenvironmentdrastically.InWestAsia,climates, environmentalelementswithheavybuildingsandshadedcourtyardsarecommon.Theseclimatestypicallyhaveahuge diurnaltemperaturerange,andhousestendtoemployanarrangementofthesemeasures,withtheparticularmixbeing modulatedtosuitlocalmicro-climaticcharacteristics.Selectingandspecifyingenvironmentalbuildingmaterialsareoften complicatedprocesses(Jester,1995).

Buildersfromthisregioncreatedtheirhabitatstakingintoconsiderationtheabove-mentionedquestion,inanefficient mannerandtofithumanneedsbyadaptingtolocalenvironmentalparameters.Eachbuildingmaterialdisplaysthedifferent physicalcharacteristics;thestructurerequiresrigidstrengthtosupportthedeadweightoftheroofandwalls.Ifthesituation dictatestherangeoffittingmaterials,togethertheycommandtheform.WestAsia’svastlandmassesarediverseingeology and climate(Almusaed,1997). Thisinvestigationhastofind suitablesolutions for buildingmaterialsand then study differentbuildingmaterialsfromvarioussourcesandbasedonitscharacteristicsofeco-energyhouseefficiency.Themain lessonwecanlearnfromthisstudyisnotonlytofurthertheconservationandrepossessionoftheformofhabitatsalreadyin existence,butalsotorethinkwhatcanformnewhabitatsforthefuture(Fig.1).

2. Climate-specificeffects

ClimateisthemainfactorthatdirectlyaffectstheconstructionprocessandbuildingmaterialsinWestAsia.Thisregionis situatedinthesubtropics’climatezone.Itisaffectedbythesubtropics’high-pressurebelt,whichreachesthefarthestnorth inthesummer.TheskyinWestAsiaisbrightandglaring,evenwhenthinlyclouded.Asonegoesinlandfromtheequator, seasonaldifferencesinclimatebecomemoremarkedwithawetterwetseason,andadrierwinterperiod(Kukreja,1978). TherearemanyfactorsthataffectbuildingmaterialsoftraditionalbuildingsfromWestAsia.Solarradiationdeteriorates organicmaterialsbyinitiatingchemicalreactionswithinthematerialandcausingoxidation.Fig.2showsthemonthly averagetemperatureandsunshinehoursintheWestAsiaRegion.Inthisregion,edificeshavetobeplannedwithgreat attentionandthought,andwithduerespectforclimate.Shadeandprotection fromduststormsmayhavethehighest priorityinsomeareas,whereasinotherareas,ventilationandthetrappingofairstreamsandbreezearetheprimarygoals. Theeffectofclimateoverthebuildingmaterialsislarge;hightemperatures,forexample,canaffectalltypesofmaterialsin general.Thespeedofachemicalreactiondoublesforevery108Cincreaseintemperature(Nielsen,2010).

Inaddition,increasinglevelsofhumiditycanincreasethedeteriorationphysicallyandbycreatinganenvironmentfor harmfulfungus andmicrobial growthaswellasinsectattacks.Changesinhumidityalsocausedeterioration through changesinvolumeandstresswithinthematerial.

3. Investigationmethods

AN environmental profile is achieved on thebasisof theSBI (DK) calculationprogramme, BEAT2000, which is a standardisedtechniqueforclassifyingandmeasuringtheenvironmentaleffectsrelatedtobuildingmaterialsintheirlife

cycles(11).Itconsistsofsevenparametersthatcoverallessentialphysicalenvironmentalimpactsandeffects.Itispossible toexamineanenvironmentalprofile indicatorusingthesameindicatoronanotherone.Thefirstindicatorisresource consumption,wheretheenvironmentalimpactsofresourcebenefitscanbecomposedofalossofresourcesandspace consumptionandrisksofgasextractionoracultivationprocess.Thestudywillusethreecircumstances.Thefirstisthe abilityofthematerialtoengageinarecyclingprocess,whereitcanprovidefortheimmediateenvironmentbyreducingthe useofnewresources.Knowledgematerialsareapartoftherenewableresourceprocess,suchas,inthebuildingofplant materials,mainlywood,ornon-renewableresources,suchasmineralsubstanceslikebrick,concreteandmetals.Thesecond indicatoristheenvironmentalimpactofenergyconsumption.Inthissituation,thestudywillusethreecircumstances: renewablefeedstock energy, theheat of combustionof renewableresources, whereis woodisthe principal base product; non-renewable feedstock energy, such as plastic; and renewableenergy, such as energy from wind and hydropowerproductionandbiofuels.Lastisnon-renewableenergy, suchascoal,oil,gas.Theseenergysourcesare characterisedbyalimitedquantityatdisposal,andtheirusegivesriseto,amongotherthings,thegreenhouseeffect. Thethirdindicatorisagreenhouseeffect,whichshowstheenvironmentalimpactofgreenhouse-gasemissions.The anthropogenicgreenhouseeffectisduetocordgases(includingcarbondioxide,methaneandother)fortheretention trapsheatradiationthatwouldotherwiseradiatefromtheearthintospace.Inthisway,theycontributetoatmospheric warming. Acidification influence is a fourth indicator that shows the environmental impact of the emissions of acidifyingcompounds(mainlysulphurdioxideandnitrogenoxides),whichattackplantfoliageandacidifythesoil. Nitrogenimpactisafifthindicator,whichshowstheenvironmentalimpactofthedischargeofsubstancescontaining nitrogenorphosphorus.Theycancausethegrowthofalgaeorplantstoincreaseoutofbalanceinrelationto,andtothe detrimentof,theglobalecosystem.Thetoxificationeffectisasixthindicatoroftheenvironmentalprofile,showingthe environmentalimpactoftheemissionsofsubstancesthathaveacuteandchronictoxiceffectsonhumans.Disposability isthelastindicatorofenvironmentalprofilesandshowswhathappenstoabuilding,structureormaterialonceitslifeis over.Inthissituation,thestudywillusethreecircumstances:recycling/high-valuerecycling,thedirectreuseofthe materialinitsoriginalform orreuseofthematerialinnovativelythroughtheproductionofnewmaterials(Marsh, 2000).Alow-worthrecycling/incineration,therecyclingofmaterialfortheproductionofbrandnewmaterialsoflower quality,orburningthematerialwithenergy;andhazardouswaste,wherethematerialcontainssubstancesthatmustbe disposedofaccordingtolaw(Table1).

Comparisonsareaninstrumentofinquiry.Materialsrelatedtoenvironmentalimpactscanbeassessedinrelationtoother factorssuchasenergyconsumptionandthegreenhouseeffect,whichisdividedintothefollowing:

Materials Acclimatisation

Amaterial impacton theenvironment shouldnot beobserved in isolationfrom otherenvironmental factors.The environmental impact of certain materials or structures can be compared to other factors (Dinesen, 1997). The environmentalprofilecancomparetheenvironmentalimpactperm2-floorareasofthehouse’sacclimatisationneedsandits buildingmaterials.ThecalculationofhousingaccumulationrequiresusingtheapproachdevelopedbySBIforthecalculation programmeBV95.Thecalculatedcooling&heatingrequirementsarethenconvertedtogrossenergyconsumptionandCO2

emissions.

4. Specificbuildingmaterialsnominated

Abuildingisbuilttobeoccupiedbyhumans.Assuch,itmakessensethatarchitects,betheyClassical,Renaissance, Modern,orcontemporary,wouldusethehumanbodyasinspirationoraprincipleofdesign(Korydon,2012).Thebuilding envelopeisaman’sbarrieragainstexternalatmosphericconditionsandtheirfluctuations.Buildersfromthiszonehave chosenthreevariedcategories,inthebuildingmaterial’sselectingprocess.Thesearemineralmaterials,organicmaterials andmixturematerial.

4.1. Organicbuildingmaterials

Thisisthefirstbuildingmaterialutilisedbyhumanbeingsinthebuildingprocess.Itcomesfromrenewableresourcesand canbeextractedbyhumanseasily;therefore,itisanecologicalmaterialwithmanygoodproprietiesandcanbesuccessfully usedintheconstructionprocess.Itisalargepartofhumanlife(Brown,1990).Itisapopularbuildingmaterialbecauseofitis specificenvironmental friendlinessandgreat energyvalues. Themainbenefitsofthesematerialsaretheir cheapness, prevalence,andexcellentproprietiesofthermalandacousticalinsulation.

4.1.1. Reeds

Reedisanorganicbuildingmaterial;ithasgoodresistancetowateractions.Itcontainsahighratioofsiliconsubstance, whichleadstoitbeingdurableandflexibleintechnicalactionandstructures;however,itisahighlyflammablematerial.The highconcentrationofsilicainthereedsmakesthismaterialunattractiveforinsectsandotheranimals.Reedmeetsallthe requirementstobeanefficientinsulator.Theformofthestemallowsittoserveallmannersoffunctions(Elias,1980).Itisan excellent thermal and acoustic insulator material. Therelative durability and flexibilityin construction are themost importantproprietiesofreeds.Theuniquepropertiesofreedshavebeennotedforalongtime,inallregionsoftheworld (Lauren,2000).Theinfluenceofreedsonpathogenicbacteriaisparticularlyintense.Reedsfromthemarshlandregionconsist ofseveraltypesofplantswhosestemsdifferinthickness,flexibilityandchemicalcomposition.Themostpopularreedsused intheconstructionprocessare‘‘Ihdri’’,theregionalnameofthistypeofreed.Thebuildingofwallswithreedsismuchless labourintensivethanthatwithothermaterialssuchasbrick,adobe,orstone,andrequiresconsiderablylessskill.Reed buildingisforgiving,encouragesindividualcreativity,andleadstofinalstructuresthatareclimaticallyadaptedandenergy efficient.Reed does havesomedisadvantages. Itsnatural durability is lowerthan wood,and it mustbe treatedwith preservativestolastinexposedlocations.

4.1.2. Straw

Strawisamaterialwithhighthermalefficiency.IthasanR-valuesubstantiallybetterthanthoseofothertraditional buildings,dependingonthetypeofstraw;itconsistsofbarleythatis36%cellulose,26%pentoses,17%linen,wax,proteinand ash–acompositionverysimilartowood.Thestrawhasexcellentinsulationproperties.Straw’sbiologicalfunctionsinclude itsaxisforwater.Therefore,strawbalesaregoodattransportingmoistureandthusregulateinteriorhumidity,providedthey bearthediffusionthroughopenscreenandcoatings.Straw’sweaknessesareriskoffire,insectsordecayrefractioncausedby long-term,highmoisturecontent(Gillv,1970).Strawcanprovidegreatlyimprovedcomfort,anddramaticenergysavings comparedtomoreexpensivetraditionalbuildingstructuresbecausetheyallowforsmallerheatingorcoolingsystemsin conventionalhomesbecauseoftheincreasedinsulation.Balebuildingisofparticularvalueinsevereenvironmentswhere energyiscostly.

4.1.3. Wood

Woodisanorganicmaterial,anaturalcombinationofcellulosefibres(thatarestrongintension)embeddedinamatrix that resistscompression(Janssen,1988). Theprincipalcomponentsinwoodarecellulose (40–50%)andhemicellulose (15–25%),withlignin(15–30%)aswellasothermaterialsuchassugar,starchandprotein.Thetechnicalpropertiesofwood arehighlydependentonthetypeandmoisturecontent.Italsocontainsvaryingotherelementsdependingonthetype, Table1

Environmentalprofilesindicatorsusingineco-energybuildingsmaterialsefficiencyanalysis. Environmentalprofilesindicators Analysisfactors

Resourceconsumption Abilitytorecycling process(ARP.)

Renewableresources(RR) Nonrenewableresources(NRR) Energyconsumption Renewablefeedstock

energy(RFE)

Non-renewablefeedstock energy(NRFE)

Renewableenergy(RE) Nonrenewable energy(NRE)

Greenhouseeffect GE

Acidificationinfluence AI

Nitrogenimpact NI

Intoxicationeffect IE

whichdefinesitssmell,colourandresistancetopestdamage.Therearetwoformsofwood,softwoodandhardwood,which aresubdividedintoanumberofdifferenttypes(EdwardandJoseph,2011).

Woodhasahighcaloricvalue(between12.5MJ/kgand20.1MJ/kg).Thermalre-utilisationofuntreatedanduncoatedwood isun-problematic.Re-utilisationispossibleifthewoodisdismantledwithoutdamage.Untreatedoldwoodconventionallycan beusedasrawmaterialforanumberofdifferentapplications(Woolley,2006).Theconversionofwoodintoasustainable, renewableresourcetobeusedasamainbuildingmaterialcouldbebeneficialinvariousareasoftheworld.

4.2. Mineralbuildingmaterial

Mineralmaterialsaremadefromnon-renewableresourcesdugon landoratsea. Theyarehomogeneous,naturally occurringsolid inorganicmaterialswitha clearcrystalstructure anda definite chemicalcomposition(Damon, 1983). Buildersfromthiszonehavefoundgoodbuildingmaterialsfromthelocalneighbourhood.Twoessentialbuildingmaterials wereselectedinthebuildingprocess:clayandbrick,whichareneartherequiredscaleofhumans.

4.2.1. Clay

Today,clayofferstheonlypracticalprospectforbuildingthefivehundredmillionhousesthatwillberequiredinthe comingyears(Anil,1981).Amassofclayhasextraordinaryformabilityandrobustness.Excellentadhesionandbonding forcescountasthemainpropertiesofclay.

4.2.2. Brick

Brickisusedas aprincipalbuildingmaterialfromzone‘‘I’’. ThetypicalhousefromSumerianagewasa one-story constructionmadefrombakedorsun-driedmud-brick.Thefamilyhouseincludedthefollowingstructurefunctions:aliving room,kitchen,opencourtyard,servant’sresidences,etc.Abrick-buildingelementhasexcellentthermalresistance(Barry, 1988).

Thematerialisveryefficientinenergyconsumptionandcanbeacceptedasabio-ecologicalmaterial,especiallyinWest Asia.Claybricksareamorethermallyinertmaterial,andchemicalreactionsarerelativelylow.Thus,theeffectsofgreen housesarelimited(Manandhar,1983).Therecyclingofclaybrickscanbeadifficultprocessduetotheunavoidablemortar, renderandplasterresiduethattendstoadheretothebricks,particularlywhensuchproductshavehighcementcontent. However,olderbrickiseasiertorecyclebecausemuchofitwasconstructedusinglimemortar(Manfredetal.,2006). 4.3. Mixtureofbuildingmaterials

4.3.1. Clay+straw

Thisisoneoftheancientbuildingpracticesknown.Clayisodourless,non-toxicandpleasanttoworkwithincombination withstraw,creatingasofttopulpypreparedmixofclayandvegetablefibres(straw)thatcanbeusedforfillingthepanelsin timber-framedbuildingsorpressedinmouldsformakingclaybricksandboards.Ready-mademixesarenowavailableon themarket.Thedensityofthemixturebuildingmaterialofclayandstrawis1200–1700kg/m3_{.Amixofclayandstrawisa}

heterogeneousmaterial,withgoodthermalproperties(Easton,1996).Fig.3showstheenvironmentalprofilecomparative analyticalinterpretationofenvironmentalprofilesof1m2ofdifferentbuildingmaterials.

Thestraw–claymixcreatesaunique,breathablecombinationofhighinsulationwiththermalmass.

Fig.3.Comparativeanalyticalinterpretationofenvironmentalprofilesof1m2

5. Buildingsystemsofheritagepractices(casestudyfromBasrahabitats)

ThecityislocatedinaregionofthehistoricareaofSumer,thehometownofthefictionalcharacterSinbadtheSailor,anda suggestedplaceoftheGardenofEden.Itheldasignificantpositionintheearlyregionalhistoryandwasfoundedin636AD.It includesthreedifferenthabitatarrangements.Thefirstappearedinthenorthpartofthecityinthezoneofmarshes,ZoneIII. Anothertypeappearedinthesouthpartofthecityinthedesertarea,ZoneII.Thelastappearedthemiddlepartofthecity besidethebig-cityriverShatAl-Arab,ZoneI,asshowninFig.4.

Fromthepractical experiencesofthebuildingprocess,specifichabitatunitsfromhistoricalexperiencesweremore relatedtotheobjectivecontext(SolarHandbook,1986).Oneofthemosteffectiveinterventionsofanoldbuildingfromthis regionwasrespectingbalancesbetweenmanyenvironmentalfactorstocreateaparticularbuildingstyle,whichmakesthe balances between humanlife and themilieu condition optimal. The notion of ecological buildingis not an absolute (Almusaed,1996;Marsh,2000).Itis,therefore,morecorrecttousethewordsmoreorlessenvironmentallyfriendly,healthy orwillingecology(DoranandCather,2013).However,thatisnotsufficientinpracticalexperience.Accordingly,oldbuilders of thecity andregion tookintoaccountmany otherfactors.Oneimportantfactor wastheimplication ofbio-climatic conceptsinthebuildingprocess

-Whyabio-climaticbuildingconcept?

Theclimatehasaprimaryinfluenceonarchitecturalform,notonlyinthechallengesitposestothebuilderbutalsoin the materials it supports. In bio-climatic building conception, the edifice is converted to a subsystem of a vast environmentalsystemthatshouldbeexaminedcarefully.Theholisticintegrationofsubsystemsinthesystemiscritical. Thereareclearinterpretationsinnativearchitecture(HoubenandGuillaud,1984).Thetemperatureofthegroundorwalls canbesubstantiallydifferentfromthatoftheneighbouringatmosphere.Inbio-climaticbuildingsfromBasra,theearthis valuableasashelter,particularlyinconjunctionwithlandscaping.

-SpecifichousesFromBasra

Basra’straditionalhabitathasevolvedwithintheseconstraints;itcanbedefinedasarchitecturewithoutarchitects:not thatitiscreatedwithoutoverallsupervision,justthatitisnotinthehandsofasophisticatedurbanprofessional.Instead,it isvernacularinthatitistheproductofwell-triedlocalcraftsmenraisedintheuseoflocalmaterialstoconfrontlocalsocial andenvironmentalconditions.GlazedwindowsarenotpartoftheBasratradition.Inthewarmerregions,glassinhibitsthe flowofairinsummer.Openingsaresealedagainstthewintercoldbyopaqueshuttersorclothscreens.Ruralhousingoften lackswindowopenings,makingforadarkinterior(Namdin,1996).Buildingmaterialsareconvenient,readilyavailableand canbemadeandusedbythecitybuilderstobuildtheirhabitats.Inallhousing’models,theallocationofhabitatfunctions inthehouseresemblestheshapeofatree,wherethemainbuildingelementisacourtyard,whichispoint‘‘zero’’inthe housestructure.Themostcommoncharacteristicofthehousesofthehotandhumidregionsistheiropenness.Theyare constructedtocatcheverybreezethatoccurs,fornaturalaircurrentsarethebestreliefinhumidclimates[8-2].Allhabitat functionsareallocatedaroundthecourtyardwithahierarchyapproach.Themostimportantisforfunctionsofliving,such asalivingroom.Nextcomeserviceareas,suchaskitchens.Inthisstudy,weinvestigatedthreedifferentcaseswhereold buildersconstructedsomethingappropriatefortheenvironmental,climaticandhumanrequirements.

5.1. ‘‘OldBasraHabitat’’fromzoneI

Ahightemperature,‘‘T’’,duetotheheatislandphenomenonisamajorriskfactorthataffectshousingconfigurationsand compositionsinthiszone.Therecommendationistocreateahabitatunitthatadaptstoextremeclimatewithaseriesof

interferences such as significant thermal insulation, profound shadows on facades, and natural stream ventilations throughoutthebuildingfunctionsandstructures(Fig.5).

5.1.1. Thehousemechanism

InOldBasra,ahouseisconsideredbeautifulifitiscapaciousandifthesituationisairyandexposedonallsidestothe wind,especiallytothenorthernbreeze.Ahealthyhousehasitscourtyards,basinsofwater,andwoodenpiecesonthe frontofthefac¸ade‘‘Shanashil.’’Ahandsomehouseisseenwithoutterraces,with‘‘Shanashil’’onwhichthefamilymay sleepduringthenight(Fathy,1986).MostoftheoldBasradistincthabitatsaredecorated,usuallytoshowinvisiblespirits anddemonsandtosatisfylocaltraditions.Buildingmaterialshavetobestrictlyrespected(seeFig.10).Thehabitatareais dividedintotwofunctionalzones:asocialareathatincludesthelivingroom,kitchen,storageroom,andbathroomanda privateareathatincludesbedrooms.Communication betweenalloperationalareasoccursthroughoutthecourtyard (Table2).

5.1.2. Technicalhousedescription

Thehabitatareaofthisedificeisca.125m2_{:thesocialareais30%,theprivateareais45%,andthecourtyardis25%.The}

buildingmaterialsusedinthecreationofthehouseareasfollows:

Theroofismadeof10cmofclayandstraw,whichimprovestheroof’sresistancestowaterproofingandhightemperature; 3cmofpressedstraw;10cmofreeds;5cmofpressedstrawand10cmofwoodasastructuralelement.

Thefloorismadeofa40cmlayerofclayandeventuallysandasahealthyground,anda12cmlayerofbrick. Theexteriorwalliscombinedwithaninnerwallwith24cmofbrick.

Theupperfac¸adeismadeofwoodenelements(Shanashilunit),withathermalroll. Theinteriorwallismadeof12cmofbrick.

Theestimatedlifecycleis100years.

Fig.5.TraditionalhousefromzoneI(OldBasraHabitat).

Table2

Differentmaterialusesincreatingandthepercentageofmaterialinlayers. Externalwalls (46%)of totalareas Glasspanels (1%)oftotal areas Roof(10%) oftotalarea Groundslab (15%)oftotal areas Innerwalls (13%)oftotal areas llevelslabs (9%)oftotal areas Foundation (6%)oftotal areas Materials Areas Mat. A Mat. A Mat. A Mat. A Mat. A Mat. A Brick 69% Wood 15% Clayandstraw 28% Clay 100% Brick 100% Brick 100% Brick 100% Wood 31% Glass 85% Pressedreeds 6%

Reeds 39% Pressedreeds 6% Wood 21%

5.1.3. Houseenvironmentalimpacts

This is a category of heavy construction. Brickis the main material usedin this construction. Theimpact on the environmentbyacclimatisationorbuildingmaterialsislimited.Thehousesarelocatedinrowbuildingsinfrontofanarrow street,placeddirectlybytheoldcityriver.Thehouseswerebuiltinthebeginningofthelastcentury.

TheresultsshowthatthereleaseofCO2isrelativelow;however,itishigherthanothercategoriesofhouses.Fig.6shows

theinfluenceofthegreenhouseeffectdistributedonhabitatdevelopmentandtheenvironmentalprofilefor1m2_.

Theenvironmentalimpactofthematerialsisarepresentationoftheresultsshownintheenvironmentalprofileofthe samehouse’smaterials.

5.2. ‘‘MarshesHouse,Unit’’fromzoneII

Ahighhumidity‘‘H’’,duetomarshwater,isamajorriskfactorthataffectshousingconfigurationsandcompositionsfrom thiszone.Arecommendationistocreateahabitatunitwithabuildingmaterialresistanttowaterandhumidity. 5.2.1. Thehousemechanism

Thelocationisahistoricsite,fromtheSumeriantime.Thehousingconfigurationwasfoundedforthepreliminarytimein the‘‘Ur’’city,wheretheinitialsettlementwasfounded(IlayandBarry,1998).UNESCOrecognisesthelacustrineregioninthe northofBasraasamonumentofnature,representingoneofthelargestsitesofuniqueecosystemtypesintheworld.Thereis alowdensityofpeoplelivinginsymbiosiswithimpressivefloraandfaunafullofrarespecies.InthenorthofBasra,onan ‘‘ArtificialIsland’’,thehousewasbuiltinwaterwithaweakcurrent,andthehabitatunitismadeofreedsandamixedofclay andstraw(Tobiasetal.,2009).Therearetwowaystomaketheislandsuitablefortheconstructionprocess:oneischoosing goodgroundandtheotherismakingitsuitableforaparticularcase.Fig.7showsthedifferentproceduresforbuildingan artificialisland.

5.2.2. Technicalhousedescription Thehabitatunitareais147m2₍₇

21)m:

Thehabitatentranceisorientedtowardsthenorthwest,wherethedominantwindoriginates.

Fig.7.Differentpositionofartificialislandmadeforhabitatunit(Abbas,2012). Fig.6.Thegreenhouseeffectspreadonhabitatconstructionandenvironmentalprofilefor1m2

Thefrontalfac¸adesontheaxis(northwest-southeast)areperforatedtoallowforpermanentnaturalcross-ventilation (seeFig.8).

Theminimumdistancetothewatermustbeapproximately10m. Theroofisalwaysmadeofavaultform.

Thenumberofcolumnsonthelongsideisasfollows:sevenpillarswiththelocalnameofShabe,with3mbetween 2pillars.

Thefacadehasfourpillars:theroofpillarsframingtheentranceandtheotherslocatedonthecorners. Theestimatedlifecycleis25years.

Thehabitatsiteiscreatedfrommanypoststhatincludecloselyrelatedstrainsofreedsbetweenthem.Theheightofthe pillar(Shabe)canreach10m.Thediameterofthepillar(Shabe)isapproximately70cmatthebaseand20cmatthetop(Fig.9). 5.2.3. Thehouse’senvironmentalimpacts

Thehouseismadeoflightweightconstructions.Theprincipalbuildingmaterialappliedisreed.Table3showsdifferent materialusedinthecompositionandthepercentageofbuildingmaterialsinlayers.

A demonstrationshows that housesmade of reeds are friendlier environmentally, with a positive impact on the environmentandlessenergyconsumption.Ashortlifecyclematerialpresentsnegativeaspectstoabuildingsystem.Fig.10

showsthegreenhouseeffectforahabitatconstructionandtheenvironmentalprofilefor1m2_.

5.3. The‘‘Al-ZubeirHouse,Unit’’fromzoneIII

Thesandywind‘‘W’’,whichisduetotheSaharaDesertenvironmentintheArabianPeninsula,isamajorriskfactorthat affectshouseconfigurationsandcompositionsfromthiszone.Here,ablindwallisrecommended.

5.3.1. Thehousemechanism

Inmanyways,theearthisthemostprominentmaterialusedinnaturalbuildings.Earthcanbefoundeverywhere,and,as aresult,itusedtobesaidthatthemajorityoftheworld’spopulationstilllivedinearthbuildings(Keefe,2005).Ofcourse, concreteandbricksaremadeofmaterialfromtheearth,butwhatwillbediscussedherearestructuresthataremadeofearth initsmostnaturalstate,withaminimumamountoftreatmentorprocessing(Wenzel,1996).Strongprevailingsandywinds provokeabuilder’sresponse,resultinginlower,blindfac¸ades,flatterbuildingsofferinglessresistanceandthuslessproneto buildingdamageandhumandiscomfort.Experiencesfromtheoldbuildingprocessshowthatmalleablebuildingmaterials canbeemployedwhentheclimateishumidandarerigidwhentheclimateisdry.Usuallywetclayisuseddirectly,mixed withStraw,andperhapsgivenmorebodybyaddinggravelorstone.Thisisprominentinareasoftheworldwhereearth

Fig.9.CompositionsReed’shousesuchprincipalbuildingmaterialsfromnorthernandEasternpartofBasra.

Table3

The‘‘MarshesHouse,Unit’’compositions,areasandpercentage. Externalwalls (58%)oftotalareas Openingorifice (2%)oftotal areas Roof(16%) oftotalareas Groundslab (9%)oftotalareas Innerwalls (12%)oftotal areas Foundation(3%) oftotalareas

Materials Areas Mat. A Mat. A Mat. A Mat. A Mat. A Reeds 90% Reeds 15% Pressedreeds 5% Clayandstraw 80% Reeds 100% Reeds 100% Pressedreeds 10% Orifice 85% Reeds 90% Pressedreeds 20%

Pressedreeds 5%

Fig.10.Thegreenhouseeffectdistributedonhabitatconstruction,andenvironmentalprofilefor1m2

buildingsmayhavearelativelyshortlifeaspartofanomadicexistence.Whenabandoned,theywillnotleaveanything unpleasantbehind(Wenzel,1996).Theextractionofclay,especiallyonasitewhereahouseisduetobecreated,isa zero-carbonsolutionforconstruction,andclayandstrawwallsandfloorscanbeusedasadirectsubstituteformassconcrete (MarchellandLeary,1974).

The‘‘Al-ZubeirHouse,Unit’’building,initsarchitecturewithoutarchitects,notesthatinexperiencedbuildersfittedtheir worktothelocalenvironmentand topography.Basra’svast varietyofenvironmentsandlocalmicroclimateassures a correspondinglywiderangeofareply.Thebeautyofthe‘‘Al-ZubeirHouseUnits’’designderiveslessfromself-conscious decorativeattemptsthanfromunadulterated,practicaloutlinesproducedbyadaptingregionalmaterialtobeaseconomical aspossible,resistingaggressiveenvironmentalelementsandemployingbeneficialones.HabitatsfromanAl-Zubeirdistrict aretrulyvernacular,utilisingonlyslightlyalteredmaterialfromitsimmediatesurroundings.Rural,desertarchitectureis remarkableforitssculpturalshapesachievedinclay.

5.3.2. Technicalhousedescription

Inthiszone,edificeshavetobeplannedwithgreatattentionandthoughtandwithduerespectforclimate.Shadeand protectionfromduststormsmayhavethehighestpriorityinsomeareas,whereasinotherregions,ventilationandthe trappingofaircurrentsandbreezearetheprimaryconsiderations(Kukreja,1978)(seeFig.11).Thecourtyardspaceisan essentialelementinthehabitatfromzoneIII,whereallhabitatfunctionsareallocatedtogetherandareorientedtowardsthe courtyard.Intimacyisnecessaryinculturallife.Allprimaryfunctionsareorientedtowardsthehousecourtyarddirectly.The unitinvolvesjustonelevel(Fig.12).

Fig.11.AcompositionsclayandstrawaremainbuildingmaterialsfromnorthernandEasternpartofBasra.

Fig.12.Thegreenhouseeffectdistributedonhabitatconstruction,andenvironmentalprofilefor1m2

Thehabitatareaofthisedificeisofca.450m2_{,wherethesocialareais10%,theprivateareais35%,andthecourtyardis}

55%.Thebuildingmaterialsusedintheconceptionofthehouseareasfollows:

Theroofismadeofthemixtureof10cmofclayandstraw,3cmofpressedstraw,10cmofreeds,5cmofpressedstrawand 10cmofwoodasastructuralelement

Thefloorismadeofa30cmlayerofclayandeventuallysand,asasolidbase,anda10cmlayerofclayandstraw. Theexteriorwalliscombinedwithaninnerfacelayerof3cmspecialclayandstraw,or25cmofclayandstrawandthe

sameinnerfaceof3cmclayandstraw.

Theinteriorwallismadeof15cmclayandstraw. Theestimatedlifecycleis50years.

Habitatshapesvaryfromarectangularplanandextensiontothenorthtoasquareone.Theconglomerationofbuildings createsaprogressionofprivatespace,whichisenclosedbyaclaywall;therefore,acourtyardiscreatedbythisprocess (Jensen,1997).Thesystemwasdevelopedforindividualutility,freeoffixedrules.Eachbuildingisorientedinrelationtoits neighbours.

5.3.3. Houseenvironmentalimpacts

Theprincipalbuildingmaterialappliedisclayandstraw.Table4showsthedifferentmaterialusedinhousecompositions andthepercentageofmaterialsinlayers.

Thehousematerialcomponentsareenvironmentallyfriendlyandbetteremployedinenergy-efficiencyfeatures.

6. Conclusion

Definingthequalitiesofanenvironmentis neithereasy norabsolute.Theyvarywithtimeand changeaspeople’s expectationsandeducationchanges.Moreover,adaptingtoanew-architecturalideawithavernacularconceptionisdifficult formanyarchitectswhohavebeeneducatedinaculturethatdespisestheaestheticsofwhattheyseeas‘twee’vernacular cottages. Incidentally,the aesthetic and functional housing opportunitiesremain innumerable and fun opportunities. Respectisgivenahighpriority.Strategiestoreduceenvironmentalimpactscanandshouldvarydependingonthesite.The selectionofbuildingmaterialsis,overall,crucialbecausethereislittledifferenceinthematerial’senvironmentalimpacts andbecausetheyplay avitalrolebotharchitecturallyandintermsoftheimpactontheexternalenvironmentneara residential use.For instance,the term‘‘environmentallycompatible’’suggeststhat acceptableeffects for humansand ecosystemscanstillbeachievedwithmaximumamountsofemissionsandlimitedcontamination.Thisstudydiscussesthe requirementsofbuildingmaterialssuitableforbio-climaticbuildinginWestAsia,wherethemeaningofthecontemporary buildingcategory isanapplication ofthebio-climaticconcept,which isvery complex.Everywhere,sustainablehome thinkingabouttheenvironmentalimpactsintheoverallprocessesisimplicitinhouses.

Basrahadthreedifferentmicroclimates(amarshlanddistrict,desertregionandregularhotclimateinthecitycentre). ThisstudytriestoinvestigateanexistinghabitatintheIraq–Iranareathathasdifferentmicroclimates.Vernacularbuilding materialssuchasclay,brick,strawandwood,arethemostpopularbuildingmaterialsusedinthisregion.TheEcologyof BuildingMaterialsisachallengeregardingthepossibilitiesforexistingmaterialsandtheevaluation ofnewmaterials. Nevertheless,acompleteecologicalstructuredoesnotexist.However,abuildingcanalwaysbemademoreecologicaland lessenvironmentallyimpactful.Theprincipalconclusionofthestudyshowsthat:

i. Thelocalmicroclimatedirectlyinfluencestheconformationofhabitat.Therefore,thechoiceofbuildingmaterialstakesa highpriorityinthebuildingprocess.Clayandstraw,breeds,andbrickaremostfrequentlyappliedbuildingmaterials. ii.Naturalmaterialswereusedefficientlyinvernacularhouses.Itisclearthatwheninsulatinghabitats;theinterrelated

environmentalimpactoftheselectionofinsulationmaterialsisnotrelevantcomparedtothesavingsinenergy. Table4

The‘‘Al-ZubeirHouse,Unit’’compositions,areasandpercentage. Externalwalls (52%)of totalareas Glasspanels (1%)oftotal areas Roof(14%) oftotalareas Groundslab (16%)oftotalareas Innerwalls (12%)oftotalareas Foundation (5%)oftotal areas Materials Areas Mat. A Mat. A Mat. A Mat. A Mat. A Clayand

straw

100% Wood 15% Clayandstraw 28% Clayandstraw 100% Clayandstraw 100% Brick 100% Glass 85% Pressedreeds 5%

Reeds 39% Pressedreeds 7% Wood 21%

iii.Acclimatisationhasagreaterimpactontheenvironmentthanbuildingmaterials.

iv.Heavymaterials(Bricks)usedintheexteriororinteriorreduceenergyrequirements.Incontrast,clay-andreed-based materialshavealowermaterial-relatedenvironmentalimpact.

v.Tosupportthemeaningofthebuildingintheresidualvalueoftheprimaryfabric,maintenanceandrepairsmustbe carriedoutonallcomponentscorrespondingtotheirspecificrenewalcycles.

vi.Forfutureresearch,thelifecycleofbuildingmaterialsbyfocusingontheexperiencesofvernacularhousesfromthiszone shouldbeincreasedthecreateacreativeinterventionwhereinnovativematerialcanbeusedinnewbuildingswithan increasinglifecycleofcurrentmaterials.

vii.Brick,clay and woodenconstructionsshouldbe improvedtooccupy amore considerableplace inourresidential buildingsthantheydotoday.

Theobjective ofthestudy is toassistarchitects anddesigners in selecting suitablesolutions in terms ofbuilding materials.Inadditiontostudyingdifferentbuildingmaterialsfromvarioussourcesandtheircharacteristic,itisnecessaryto adapttotraditionalmaterialsinmodern,innovativeapplicationsandcreateagoodsolutionintermsofbuildingmaterialsfor WestAsiaspecifically.

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