1、BRITISH STANDARD BS EN ISO 14438:2002 Glass in building Determination of energy balance value Calculation method The European Standard EN 14438:2002 has the status of a British Standard ICS 81.040.20 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBS EN ISO 14438:2002 This Brit
2、ish Standard, having been prepared under the direction of the Building and Civil Engineering Sector Policy and Strategy Committee, was published under the authority of the Standards Policy and Strategy Committee on 24 June 2002 BSI 24 June 2002 ISBN 0 580 38794 1 National foreword This British Stand
3、ard is the official English language version of EN ISO 14438:2002. It is identical with ISO 14438:2002. The UK participation in its preparation was entrusted by Technical Committee B/520, Glass and glazing in building, to Subcommittee B/520/4, Properties and glazing methods, which has the responsibi
4、lity to: A list of organizations represented on this subcommittee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section enti
5、tled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Complia
6、nce with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related i
7、nternational and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN ISO title page, pages 2 to 11 and a back cover. The BSI copyright date displayed in this document indicates when the document was last issued. A
8、mendments issued since publication Amd. No. Date CommentsEUROPEANSTANDARD NORMEEUROPENNE EUROPISCHENORM ENISO14438 June2002 ICS81.040.20 Englishversion GlassinbuildingDeterminationofenergybalancevalue Calculationmethod(ISO14438:2002) VerredanslaconstructionDterminationdelavaleurdu bilannergtiqueMtho
9、dedecalcul(ISO14438:2002) GlasimBauwesenBestimmungdesEnergiebilanz WertesBerechnungsverfahren(ISO14438:2002) ThisEuropeanStandardwasapprovedbyCENon5March2002. CENmembersareboundtocomplywiththeCEN/CENELECInternalRegulationswhichstipulatetheconditionsforgivingthisEurope an Standardthestatusofanational
10、standardwithoutanyalteration.Uptodatelistsandbibliographicalreferencesconcernings uchnational standardsmaybeobtainedonapplicationtotheManagementCentreortoanyCENmember. ThisEuropeanStandardexistsinthreeofficialversions(English,French,German).Aversioninanyotherlanguagemadebytra nslation undertherespon
11、sibilityofaCENmemberintoitsownlanguageandnotifiedtotheManagementCentrehasthesamestatusasthe official versions. CENmembersarethenationalstandardsbodiesofAustria,Belgium,CzechRepublic,Denmark,Finland,France,Germany,Greece, Iceland,Ireland,Italy,Luxembourg,Malta,Netherlands,Norway,Portugal,Spain,Sweden
12、,SwitzerlandandUnitedKingdom. EUROPEANCOMMITTEEFORSTANDARDIZATION COMITEUROPENDENORMALISATION EUROPISCHESKOMITEEFRNORMUNG ManagementCentre:ruedeStassart,36B1050Brussels 2002CEN Allrightsofexploitationinanyformandbyanymeansreserved worldwideforCENnationalMembers. Ref.No.ENISO14438:2002EENISO14438:200
13、2(E) 2 Contents page Foreword3 1 Scope4 2 Normativereferences.4 3 Symbols .4 4 Basicformula 5 5 Basicmaterialproperties .5 6 Solarradiationincident, H p 6 7 Degreedaydata, D p 6 8 Periodofapplication, p 6 9 Principalvaluesandpresentation .6 10 Alternativesimplificationofprincipalvaluesandpresentatio
14、n 7 AnnexA (informative) Examplesofclimaticdata p, Dpand Hp8 AnnexB (informative) Examplesofcalculationoftheenergybalancevalue .9 Bibliography .11ENISO14438:2002(E) 3 Foreword Thisdocument(ENISO14438:2002)hasbeenpreparedbyTechnicalCommitteeCEN/TC129 “Glassinbuilding“, thesecretariatofwhichisheldbyIB
15、N,incollaborationwithTechnicalCommitteeISO/TC160 “Glassinbuilding“. ThisEuropeanStandardshallbegiventhestatusofanationalstandard,eitherbypublicationofanidenticaltextor byendorsement,atthelatestbyDecember2002,andconflictingnationalstandardsshallbewithdrawnatthelatest byDecember2002. AccordingtotheCEN
16、/CENELECInternalRegulations,thenationalstandardsorganizationsofthefollowing countriesareboundtoimplementthisEuropeanStandard:Austria,Belgium,CzechRepublic,Denmark,Finland, France,Germany,Greece,Iceland,Ireland,Italy,Luxembourg,Malta,Netherlands,Norway,Portugal,Spain, Sweden,SwitzerlandandtheUnitedKi
17、ngdom. AfirstFormalVotetookplacewithinCENasprEN14026between20001019and20001219. AnnexesAandBareinformative. ThisstandardincludesaBibliography.ENISO14438:2002(E) 4 1 Scope ThisEuropeanStandardspecifiesacalculationmethodtodeterminetheenergybalancevalueofglazing.This EuropeanStandardappliestotransparen
18、tmaterialssuchasglassandcombinationsofglassusedtoglaze windowsinbuildings. Thismethodisintendedtoevaluatethebalanceofheatlossandusefulheatgainbysolarradiationenteringthe buildingthroughtheglazingforagivenperiodbymeansofanaveragerateofloss(orgain)ofheatcalledthe energybalancevalue. Themethodenablespr
19、oducerstocomparetheperformanceoftheirglazingproducts.Theenergybalancevalue shouldnotbeusedforenergyuseorheatingcapacitycalculationsinbuildings. 2 Normativereferences ThisEuropeanStandardincorporatesbydatedorundatedreferences,provisionsfromotherpublications.These normativereferencesarecitedattheappro
20、priateplacesinthetextandthepublicationsarelistedhereafter.For datedreferences,subsequentamendmentstoorrevisionsofanyofthesepublicationsapplytothisEuropean Standardonlywhenincorporatedinitbyamendmentorrevision.Forundatedreferencesthelatesteditionofthe publicationreferredtoapplies(includingamendments)
21、. EN410 GlassinbuildingDeterminationofluminousandsolarcharacteristicsofglazing EN673 GlassinbuildingDeterminationofthermaltransmittance(Uvalue)Calculationmethod EN674 GlassinbuildingDeterminationofthermaltransmittance(Uvalue)Guardedhotplatemethod EN675 GlassinbuildingDeterminationofthermaltransmitta
22、nce(Uvalue)Heatflowmetermethod EN832 ThermalperformanceofbuildingsCalculationofenergyuseforheatingResidentialbuildings 3 Symbols D degreedays K24h utilityfactor H unobstructedincidentsolarradiation kWh/m 2 g totalsolarenergytransmittance(solarfactor) U thermaltransmittance( Uvalue) W/(m 2 K) f facto
23、rduetoglazingmaintenanceandshadoweffects S functionof Hand Dcharacterisingagivenregion W/(m 2 K) E energybalancevalue W/(m 2 K) Subscripts p periodofapplicationENISO14438:2002(E) 5 4 Basicformula Theenergybalancevalue, E,foragivenperiodiscalculatedaccordingtothefollowingequation: p p D H f g U E (1)
24、 where: U isthe Uvalueoftheglazing; istheutilityfactor; f isthefactorduetoglazingmaintenanceandshadoweffects ; g istheglazingtotalsolarenergytransmittance(solarfactor); H p istheunobstructedincidentsolarradiationduringthegivenperiod; D p isthedegreedaytotalforthegivenperiod. NOTE Anexampleofcalculat
25、ionisgiveninannexB. 5 Basicmaterialproperties 5.1 U Value(thermaltransmittance) The Uvalueoftheglazingisdeterminedbycalculation,inaccordancewithEN673ormeasurementinaccordance withEN674orEN675. 5.2 Utilityfactor, Theutilityfactorforabuildingorspaceinabuildingistheratiooftheusefulheatgains,whichdispla
26、cethe functionalheatingoveradefinedperiod,tothetotalheatgainsduringtheperiod. Theutilityfactorisessentiallyapropertyofthebuildingdesign. Theutilityfactorcannotexceedunity.Itsprecisevaluedependsontheabilityofthebuildingandthecontrolofits heatingsystemstodisplaceitsfunctionalheatingloadwhilemaintainin
27、gdesirabletemperaturesinside. Theutilityfactorisdependentontheperiodchosenandthelengthoftheperiod. Itsvaluefortypicalconstructionssuchaswindowsinbuildingsliesbetween0,4and0,8forthewinterheatingperiod anditcanbedeterminedexperimentallyorbycalculationinaccordancewithEN832.Forpurposesofcomparison ofgla
28、zingproductsautilityfactorof0,6shallbeused. 5.3 Glazingtotalsolarenergytransmittance(solarfactor), g Thisisthetotaltransmissionofsolarheatthroughtheglazing,andisthesumofthedirecttransmittanceofsolar radiationandtheamountofabsorbedradiationwhichisconvectedandreradiatedtotheinterior. Thetotalsolarener
29、gytransmittanceshallbedeterminedinaccordancewithEN410. 5.4 Factorduetoglazingmaintenanceandshadoweffects, f Thisfactorisanallowanceforaccumulateddirtontheglazingsurfaceandshadingeffects.Forverticalornear vertical(15)surfacesthevalue0,8shallbeusedforcomparisonofglazingproducts.ENISO14438:2002(E) 6 6
30、Solarradiationincident, H p Theamountofunobstructedsolarradiationisdescribedbythefactor H p whichistheamountofsolarradiationin kWh/m 2 incidentupontheverticalglazingsurfaceduringthewholeperiodunderconsideration. DataforselectedsitesareexemplifiedinannexA. NOTE DataforsitesinEuropearefoundin1ofBiblio
31、graphy. 7 Degreedaydata, D p Degreedayunitsarecomputedasthedifferencebetweenthebasetemperatureandthedailyaverageoutside temperature.Oneunitisaccumulatedforeachdegreekelvintheaveragetemperatureisbelowthebase temperature.Negativevaluesarediscarded.Thisisdoneforeachdayoftheheatingperiodandsummed. Degre
32、edaydataarecalculatedforthelocalnationalconditions.Officialstatisticsarepublishedinmostcountries. Thebasetemperatureistheinternaldesigncontroltemperatureandshallbedefinedfortheperiodunder consideration.Forpurposesofcomparisonabasetemperatureof18Cshallbeused. Thevalueusedintheequationshallbethetotaln
33、umberofdegreedays(inkelvins24h)fortheperiodunder consideration.ExamplesaregiveninannexA. 8 Periodofapplication, p Themethodofthisstandardmaybeusedforevaluatingtheenergybalancevalueofglazingforanychosenperiod. Forpurposesofcomparisontheperiodisthe“heatingseason“,i.e.thewholeperiodinthemonthsduringwhi
34、ch functionalheatingisusedinthebuilding.ExamplesaregiveninannexA. 9 Principalvaluesandpresentation Fortheevaluationoftheenergybalancevalue( E)ofglazingwhichisusedforcomparativepurposesidentical underlyingassumptionsshallbemade. Alltheunderlyingassumptionsshallbestatedanddataprescribedinthisstandards
35、hallbeused. Statementofunderlyingassumptions: locationofuse; orientationofglazing; sourceofdegreedaydata. Ifvaluesoftheutilityfactorandglazingmaintenancefactordifferentfrom0,6and0,8respectivelyareusedfor purposesotherthanforcomparisonofproducts,thisshallbestated. Anypublicationofenergybalancevaluesh
36、allbeaccompaniedbyastatement,thattheevaluationisbasedonthe fullpotentialincidentsolarradiation.Anyexternalobstructionwhichovershadowsthewindowtendstoincreasethe energybalancevalue.Therefore,inadditiontoastatementoftheunderlyingassumptionsthefollowing complementarystatementshallbemade: “Thisevaluatio
37、nisapplicableonlyforunobstructedglazing“. TheenergybalancevalueshallbeexpressedinW/(m 2 K)roundedtoonedecimalfigure.Iftheseconddecimalis five,itshallberoundedtothehighervalues.ENISO14438:2002(E) 7 EXAMPLE1 1,53becomes1,5 EXAMPLE2 1,55becomes1,6 EXAMPLE3 1,549becomes1,5 10 Alternativesimplificationof
38、principalvaluesandpresentation Thebasicformulacanbesimplifiedasfollows: S g U E (2) where: p p D H f S (3) “S“maybeascribedvaluescorrespondingtoaregionoracountry,wheretheregionorcountrydoesnotextend overawidelydiverseclimaticrange.Foreachregionorcountry“deemedtosatisfy“valuesof Sfortheprincipal orie
39、ntationsareusedtocharacterisetheclimate,periodofapplicationandutilityfactoroftheincidentsolarradiation asexemplifiedinannexB.ENISO14438:2002(E) 8 AnnexA (informative) Examplesofclimaticdata p, Dpand Hp TableA.1Durationofheatingseason,degreedaytotalsforbasetemperaturesof18Candsolarradiation incidento
40、nverticalsurfacesforselectedsites Location Heating season Degree day total, D p Solarradiation, H p (kWh/m 2 ) (Duration inclusive) (K24h) North East/West South Belgium (Uccle) Denmark (Copenhagen) France ZoneH1 (Trappes) ZoneH2 (Carpentras) ZoneH3 (Nice) Germany (Hamburg) (Berlin) (Munich) Holland
41、(DeBilt) Italy (Milan) (Rome) (Messina) UK(South) (London) (ThamesValley) (Midlands) UK(North) UK(Scotland) Japan (Sapporo) (Niigata) (Tokyo) (Kagoshima) Sept/May Sept/May Sept/May Oct/May Nov/April Sept/May Sept/May Sept/May Sept/May Oct/March Nov/March Nov/March Sept/May Sept/May Sept/May Sept/Jun
42、e Oct/April Nov/April Nov/April 2900 2936 2625 2167 1542 3267 3335 3568 2935 2159 1401 844 2700 3000 3200 3757 2313 1599 1200 202 100 230 235 150 195 203 242 205 107 110 85 200 197 176 175 124 102 93 350 225 410 520 360 348 358 446 358 196 239 191 347 354 303 443 223 228 281 505 420 590 720 630 505
43、518 649 522 346 442 373 510 497 452 709 364 440 533ENISO14438:2002(E) 9 AnnexB (informative) Examplesofcalculationoftheenergybalancevalue B.1 Exampleofcalculationfromtheclimaticdata D p and H p TableB.1Examplesofclimaticdataforagivencountry,fromTableA.1 Heatingseason (Durationinclusive) Degreeday to
44、tal, D p (K24h) Solarradiation, H p (kWh/m 2) North East/West South Sept/May 2900 202 350 505 NOTEThenumericalvaluesascribedinthetableaboveareintendedtoillustratethecalculationandapplication oftheprincipleandarenotconstructedtobesimilarortypicalofanyparticularregionorcountry. Exampleofcalculationoftheenergybalancevalueforaconventionaldoubleglazing(airfilling,nolowecoating).
