Testing Buildings for Air Leakage 2000

31 Pages·2000·0.884 MB·English

by  Chartered Institution Of Building Services Engineers Staff

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00 0:232 MaTdnarom elMacinhc eETSBIC
ehT deretrahC noitutitsnI fo gnidliuB secivreSsreenignE
222 mahlaB hgiH ,daoR nodnoL 21WSSB9
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without the prior permission of the Institution.
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This document is based on the best knowledge available at the
time of publication. However no responsibility of any kind for
any injury, death, loss, damage or delay however caused
resulting from the use of these recommendations can be
accepted by the Chartered Institution of Building Services
Engineers, the authors or others involved in its publication. In
adopting these recommendations for use each adopter by
doing so agrees to accept full responsibility for any personal
,yrujni ,htaed ,ssol egamad ro yaled gnisira tuo fo roni
connection with their use by or on behalf of such adopter
evitcepserri fo eht esuac ro nosaer erofereht dna seergaot
defend, indemnify and hold harmless the Chartered Institution
fo gnidliuB secivreS ,sreenignE eht srohtua dna srehto
involved in their publication from any and all liability arising
tuo fo ro ni noitcennoc htiw hcus esu sa diaserofadna
irrespective of any negligence on the part of those
indemnified.
etoN morf eht:rehsilbup
This publication is primarily intended to provide guidance to
those responsible for the design, installation, commissioning,
operation and maintenance of building services. It is not
intended to be exhaustive or definitive and it will be necessary
rof sresu fo eht ecnadiug nevig ot esicrexe riehtnwo
professional judgement when deciding whether to abide by or
depart from it.
Typeset by CIBSE Editorial Department
detnirP ni taerG niatirB yb egaP srehtorB ,dtL ,hciwroNklofroN
Cover photograph: La Grande Arche de la Defense,
Paris — designed by Johan von Spreckelsen in 1982,
and for which air issues were critical to the success of
the project.
droweroF
Pressure testing techniques have long been used in the laboratory on building compo-
stnen hcus sa ,swodniw rof ,elpmaxe ot erusne taht niar lliw ton etartenep mehtrednu
ydniw .snoitidnoc tekraM sredael ni ygrene-wol sgnidliub evah neeb gnisu erusserp-tset
gni seuqinhcet rof lareves sraey no eht elohw detelpmoc gnidliub ot erusne a doogdliub
quality in terms of the provision of a well-sealed building in relation to air leakage.
Although the emphasis was initially on domestic buildings, there has been increasing
interest in non-domestic buildings, and in particular in industrial buildings and retail
.serots nI ,noitidda hcraeser no sgnidliub ni eht KU sah detluser ni na devorpmi-rednu
gnidnats fo ria egakael ni noitaler ot gnidliub .ngised tI sah dedivorp a esabatad noeht
egnar fo ria egakael setar taht era yltnerruc yllareneg deveihca ni ecitcarp – dna notahw
stnemevorpmi thgim eb deveihca htiw ytilauq-retteb.ngised
niatirB sah won detpecca eht naeporuE tset dradnats NErp( )92831 rof erusserp gnitsetfo
.sgnidliub sihT lacinhceT mudnaromeM stes tuo ot ebircsed woh sresu nac ylpmochtiw
eht ,dradnats dna sedivorp emos ecnadiug no slevel fo ssenthgitria ot mia rof dnawoh
eseht thgim eb.deveihca
Acknowledgements
ehT lacinhcet eton sah neeb decudorp yb eht ESBIC ksaT puorG no lacinahceM-alitneV
.noit ehT ksaT puorG srebmem:edulcni
)dtL sixA tneV( swerdnA I
)kcedomreT( maharB D
)ESBIC( tterdnurB G
)sdooW( senoJ N
)erutcetihcrA fo loohcS hsleW( )riahC( senoJ P
)dtL lanoitanretnI tloC( drofgnaL P
)ERB( bbeW B
)ATEF( nagguD M
A sucof puorg gniteem sawdleh ot edivorp ecivda ni gniraperp eht ,tnemucod dna eht
gniwollof elpoep :detubirtnoc
N rettoP)AIRSB(
R nehpetS)ERB(
S dnalroB gnidliuB( secneicS)dtL
D noswaL gnidliuB( secneicS)dtL
P namkcaJ)AIRSB(
R Harris of the Centre for Window and Cladding Technology, Bath, contributed to
xidneppA 2A no teksag.gnilaes
Contents
1 Introduction 1
2 Aim 1
3 Background 1
3.1 tahW si ria?egakael 1
3.2 yhW erusaem ria?egakael 2
3.3 riA egakael :sretemarap ria egakael xedni dna riaytilibaemrep 3
3.4 ngiseD dna noitcurtsnoc rof ria ssenthgit 5
4 Method 5
4.1 riA egakaeltset 5
4.2 gniyrraC tuo a erusserptset 7
4.3 Interpretation of data: air leakage index and air permeability 8
4.4 noitacoL fo riaegakael 8
4.5 evitceffE egakael aera 9
5 Recommended air leakage standards 9
6 Air leakage tests and infiltration rate 10
References 10
Bibliography 10
Appendices 11
xidneppA :1A naF noitasirusserp :gnitset atad sisylana ot tcerroc
to standard conditions 11
Appendix A2: Design and construction guidance 12
xidneppA :3A riA egakael tset atadteehs 14
Index 15
—
1
Testing buildings for air leakage
1 Introduction 2 Aim
noitalitneV si dedeen ni sgnidliub ot edivorp hserf riarof sihT noitacilbup sedivorp ecnadiug rof ria egakaelgnitset
,stnapucco ot etulid ,stnatullop dna ot tsuahxe taeh.sniag fo citsemod-non sgnidliub dna .sgnillewd tI sebircsedwoh
In the past buildings were, by their nature, leaky, and ot yrrac tuo a tset htiw ecnerefer ot na lanretni riaerusserp
much of the required ventilation was provided by this ecnereffid fo 05 ,aP dna eht sisylana deriuqer otenimreted
suotiutrof ria ,egakael yllausu derrefer ot sa ria.noitartlifni the two building air leakage parameters currently being
In the design and construction of modern buildings the ,desu ria ytilibaemrep dna ria egakael .xedni tI sedulcnia
aim is to provide an airtight envelope and to introduce noitpircsed fo eseht ria egakael sretemarap dna rieht esu
ventilation in a controllable way either naturally or with regards to regulatory and air infiltration modelling,
,yllacinahcem ro yb a noitanibmoc fo .htob ,revewoHeht dna sebircsed woh ot terpretni meht ot enifed nadetpecca
reality is that few buildings are sufficiently airtight to measure of air leakage. It provides recommended air
wolla siht ot .neppah sihT si ylniam eud ot eht eruliaffo leakage indices and air permeability values for
the designers and builders fully to understand and .nosirapmoc ecnadiuG si osla nevig no woh ot ngisedot
etaicerppa eht deen rof na thgitria ,noitcurtsnoc dna oteb minimise air leakage in non-domestic buildings. At the
able to achieve this throughout the design, construction time of writing, guidance on minimizing air leakage in
dna emitefil fo eht .gnidliub sihT stluser ni sgnidliubtaht sgnillewd si llits gnieb .depoleved ,revewoH ynam fo eht
allow air leakage though the building envelope and, sdohtem dna sliated depoleved rof citsemod-nonsgnidliub
because this is uncontrollable—in both quantity and nac osla eb deilppa ni.sgnillewd
location—there are often excessive rates of ventilation.
esehT ,nac ni ,nrut:rucni The guide provides recommended airtightness standards
for offices, supermarkets, industrial buildings and
— a tnacifingis ygreneytlanep .sgnillewd esehT era gnidliub sepyt rof hcihw atad.stsixe
However, other comparable building types can be
— inability of the heating system to meet comfort considered to have similar achievable air leakage rates
slevel gnidneped no rieht noitcurtsnoc.epyt
— cold draughts
— eruliaf fo eht dengised noitalitnev ,metsysrehtehw 3 dnuorgkcaB
ti eb larutan rolacinahcem
— detullop ria gniretne eht gnidliub
3.1 What is air leakage?
— decuder eulav-U fo eht.noitcurtsnoc
riA egakael si eht suotiutrof noitartlifni dna noitartlifxefo
air through a building envelope or component due to
erehT si na gnisaercni dnamed morf stneilc ot ecuderria
imperfections in its construction. It takes place, for
leakage in non-domestic buildings, and many clients are
example, through:
gniyficeps a noitasirusserp tset ta eht emit fonoitelpmoc
of construction. The BRE Building Environmental — cracks around doors, windows, panels, and
tnemssessA dohteM )MAEERB( sevig tiderc rof agnidliub gniddalc sliated
ngised fi ti si ot evah na ria egakael tset no noitelpmocfo
construction. The majority of new dwellings are built on — gaps where the structure penetrates the
speculative developments, the absence of a purchaser’s construction envelope
specification leading to little attention being given to — ecivres :seirtne ,sepip ,stcud ,seulfsrotalitnev
ssenthgitria ni taht rotces fo eht.yrtsudni
— suorop :snoitcurtsnoc ,skcirb ,skcolb ratrom stnioj
,revewoH nehw gnisaercni eht ssenthgitria fo ehtgnidliub —
tsioj snoitcennoc nihtiw etaidemretni.sroolf
,epolevne srengised tsum erusne taht etauqeda noitalitnev
is provided by the ventilation system. The requirements It can also detract from the thermal performance of a
for non-domestic buildings and dwellings differ for construction, by providing a ventilation path within the
reasons of occupation and use. Adequate means of noitcurtsnoc rof taeh ,ssol erofereht ’gnitiucric-trohs‘ eht
noitalitnev rof noitsubmoc secnailppa dna rof ehtlavomer thermal insulation, and reducing the U-value of the
fo erutsiom morf sgnillewd dluohs syawla eb.deredisnoc construction.
1
Testing buildings for air leakage
1 Introduction 2 Aim
noitalitneV si dedeen ni sgnidliub ot edivorp hserf riarof sihT noitacilbup sedivorp ecnadiug rof ria egakaelgnitset
,stnapucco ot etulid ,stnatullop dna ot tsuahxe taeh.sniag fo citsemod-non sgnidliub dna .sgnillewd tI sebircsedwoh
In the past buildings were, by their nature, leaky, and ot yrrac tuo a tset htiw ecnerefer ot na lanretni riaerusserp
much of the required ventilation was provided by this ecnereffid fo 05 ,aP dna eht sisylana deriuqer otenimreted
suotiutrof ria ,egakael yllausu derrefer ot sa ria.noitartlifni the two building air leakage parameters currently being
In the design and construction of modern buildings the ,desu ria ytilibaemrep dna ria egakael .xedni tI sedulcnia
aim is to provide an airtight envelope and to introduce noitpircsed fo eseht ria egakael sretemarap dna rieht esu
ventilation in a controllable way either naturally or with regards to regulatory and air infiltration modelling,
,yllacinahcem ro yb a noitanibmoc fo .htob ,revewoHeht dna sebircsed woh ot terpretni meht ot enifed nadetpecca
reality is that few buildings are sufficiently airtight to measure of air leakage. It provides recommended air
wolla siht ot .neppah sihT si ylniam eud ot eht eruliaffo leakage indices and air permeability values for
the designers and builders fully to understand and .nosirapmoc ecnadiuG si osla nevig no woh ot ngisedot
etaicerppa eht deen rof na thgitria ,noitcurtsnoc dna oteb minimise air leakage in non-domestic buildings. At the
able to achieve this throughout the design, construction time of writing, guidance on minimizing air leakage in
dna emitefil fo eht .gnidliub sihT stluser ni sgnidliubtaht sgnillewd si llits gnieb .depoleved ,revewoH ynam fo eht
allow air leakage though the building envelope and, sdohtem dna sliated depoleved rof citsemod-nonsgnidliub
because this is uncontrollable—in both quantity and nac osla eb deilppa ni.sgnillewd
location—there are often excessive rates of ventilation.
esehT ,nac ni ,nrut:rucni The guide provides recommended airtightness standards
for offices, supermarkets, industrial buildings and
— a tnacifingis ygreneytlanep .sgnillewd esehT era gnidliub sepyt rof hcihw atad.stsixe
However, other comparable building types can be
— inability of the heating system to meet comfort considered to have similar achievable air leakage rates
slevel gnidneped no rieht noitcurtsnoc.epyt
— cold draughts
— eruliaf fo eht dengised noitalitnev ,metsysrehtehw 3 dnuorgkcaB
ti eb larutan rolacinahcem
— detullop ria gniretne eht gnidliub
3.1 What is air leakage?
— decuder eulav-U fo eht.noitcurtsnoc
riA egakael si eht suotiutrof noitartlifni dna noitartlifxefo
air through a building envelope or component due to
erehT si na gnisaercni dnamed morf stneilc ot ecuderria
imperfections in its construction. It takes place, for
leakage in non-domestic buildings, and many clients are
example, through:
gniyficeps a noitasirusserp tset ta eht emit fonoitelpmoc
of construction. The BRE Building Environmental — cracks around doors, windows, panels, and
tnemssessA dohteM )MAEERB( sevig tiderc rof agnidliub gniddalc sliated
ngised fi ti si ot evah na ria egakael tset no noitelpmocfo
construction. The majority of new dwellings are built on — gaps where the structure penetrates the
speculative developments, the absence of a purchaser’s construction envelope
specification leading to little attention being given to — ecivres :seirtne ,sepip ,stcud ,seulfsrotalitnev
ssenthgitria ni taht rotces fo eht.yrtsudni
— suorop :snoitcurtsnoc ,skcirb ,skcolb ratrom stnioj
,revewoH nehw gnisaercni eht ssenthgitria fo ehtgnidliub —
tsioj snoitcennoc nihtiw etaidemretni.sroolf
,epolevne srengised tsum erusne taht etauqeda noitalitnev
is provided by the ventilation system. The requirements It can also detract from the thermal performance of a
for non-domestic buildings and dwellings differ for construction, by providing a ventilation path within the
reasons of occupation and use. Adequate means of noitcurtsnoc rof taeh ,ssol erofereht ’gnitiucric-trohs‘ eht
noitalitnev rof noitsubmoc secnailppa dna rof ehtlavomer thermal insulation, and reducing the U-value of the
fo erutsiom morf sgnillewd dluohs syawla eb.deredisnoc construction.
1
Testing buildings for air leakage
1 Introduction 2 Aim
noitalitneV si dedeen ni sgnidliub ot edivorp hserf riarof sihT noitacilbup sedivorp ecnadiug rof ria egakaelgnitset
,stnapucco ot etulid ,stnatullop dna ot tsuahxe taeh.sniag fo citsemod-non sgnidliub dna .sgnillewd tI sebircsedwoh
In the past buildings were, by their nature, leaky, and ot yrrac tuo a tset htiw ecnerefer ot na lanretni riaerusserp
much of the required ventilation was provided by this ecnereffid fo 05 ,aP dna eht sisylana deriuqer otenimreted
suotiutrof ria ,egakael yllausu derrefer ot sa ria.noitartlifni the two building air leakage parameters currently being
In the design and construction of modern buildings the ,desu ria ytilibaemrep dna ria egakael .xedni tI sedulcnia
aim is to provide an airtight envelope and to introduce noitpircsed fo eseht ria egakael sretemarap dna rieht esu
ventilation in a controllable way either naturally or with regards to regulatory and air infiltration modelling,
,yllacinahcem ro yb a noitanibmoc fo .htob ,revewoHeht dna sebircsed woh ot terpretni meht ot enifed nadetpecca
reality is that few buildings are sufficiently airtight to measure of air leakage. It provides recommended air
wolla siht ot .neppah sihT si ylniam eud ot eht eruliaffo leakage indices and air permeability values for
the designers and builders fully to understand and .nosirapmoc ecnadiuG si osla nevig no woh ot ngisedot
etaicerppa eht deen rof na thgitria ,noitcurtsnoc dna oteb minimise air leakage in non-domestic buildings. At the
able to achieve this throughout the design, construction time of writing, guidance on minimizing air leakage in
dna emitefil fo eht .gnidliub sihT stluser ni sgnidliubtaht sgnillewd si llits gnieb .depoleved ,revewoH ynam fo eht
allow air leakage though the building envelope and, sdohtem dna sliated depoleved rof citsemod-nonsgnidliub
because this is uncontrollable—in both quantity and nac osla eb deilppa ni.sgnillewd
location—there are often excessive rates of ventilation.
esehT ,nac ni ,nrut:rucni The guide provides recommended airtightness standards
for offices, supermarkets, industrial buildings and
— a tnacifingis ygreneytlanep .sgnillewd esehT era gnidliub sepyt rof hcihw atad.stsixe
However, other comparable building types can be
— inability of the heating system to meet comfort considered to have similar achievable air leakage rates
slevel gnidneped no rieht noitcurtsnoc.epyt
— cold draughts
— eruliaf fo eht dengised noitalitnev ,metsysrehtehw 3 dnuorgkcaB
ti eb larutan rolacinahcem
— detullop ria gniretne eht gnidliub
3.1 What is air leakage?
— decuder eulav-U fo eht.noitcurtsnoc
riA egakael si eht suotiutrof noitartlifni dna noitartlifxefo
air through a building envelope or component due to
erehT si na gnisaercni dnamed morf stneilc ot ecuderria
imperfections in its construction. It takes place, for
leakage in non-domestic buildings, and many clients are
example, through:
gniyficeps a noitasirusserp tset ta eht emit fonoitelpmoc
of construction. The BRE Building Environmental — cracks around doors, windows, panels, and
tnemssessA dohteM )MAEERB( sevig tiderc rof agnidliub gniddalc sliated
ngised fi ti si ot evah na ria egakael tset no noitelpmocfo
construction. The majority of new dwellings are built on — gaps where the structure penetrates the
speculative developments, the absence of a purchaser’s construction envelope
specification leading to little attention being given to — ecivres :seirtne ,sepip ,stcud ,seulfsrotalitnev
ssenthgitria ni taht rotces fo eht.yrtsudni
— suorop :snoitcurtsnoc ,skcirb ,skcolb ratrom stnioj
,revewoH nehw gnisaercni eht ssenthgitria fo ehtgnidliub —
tsioj snoitcennoc nihtiw etaidemretni.sroolf
,epolevne srengised tsum erusne taht etauqeda noitalitnev
is provided by the ventilation system. The requirements It can also detract from the thermal performance of a
for non-domestic buildings and dwellings differ for construction, by providing a ventilation path within the
reasons of occupation and use. Adequate means of noitcurtsnoc rof taeh ,ssol erofereht ’gnitiucric-trohs‘ eht
noitalitnev rof noitsubmoc secnailppa dna rof ehtlavomer thermal insulation, and reducing the U-value of the
fo erutsiom morf sgnillewd dluohs syawla eb.deredisnoc construction.
2 Testing buildings for air leakage
3.2 Why measure air leakage? egakael fo a gnidliub ebyam os taerg taht ehtCAVH
system cannot provide comfort conditions during
extremes of seasonal weather conditions, such as
erehT era ruof niam snosaer rof gnirusaem ria egakaelfo
when it is cold or windy. Systems are often
buildings:
’dezisrevo‘ ot tesffo seitniatrecnu ni ria.egakael
— To identify ways of reducing heat loss: The air
egakael tnenopmoc fo ,noitalitnev yllausuderrefer
ot sa ,noitartlifni nac eb .tnacifingis ,deednIemos — oT diova thguard :trofmocsid riA egakael nacevig
rise to localised draught discomfort for people
buildings are ventilated just by infiltration, with
detacol raen eht aera fo :egakael rof ,elpmaxeraen
on dengised noitalitnev ta .lla esuaceBnoitartlifni
is uncontrollable, the overall ventilation rate can ylroop delaes swodniw ro ykael.sfoor
be excessive in comparison with the fresh air
needs of the occupants. This may occur during
times of high wind speed or large differences — To control ventilation: Excessive air leakage
neewteb eht lanretni dna lanretxe ria ,erutarepmet makes it difficult to control ventilation systems.
resulting in a major increase in the heating or For example, in naturally ventilated buildings
gnilooc daol fo eht.gnidliub with trickle ventilators, excessive air leakage
detracts from their performance. Problems also
To size heating, ventilation and air-conditioning esira ni noitaler ot eht lortnoc fo eht noitacol foria
(HVAC) system-s accurately: The uncontrollable ekatni ot a ,gnidliub yas no detullop ,setiserehw
nature of air leakage can have an impact on the air leakage can provide an unplanned path for
sizing of HVAC systems. In some cases, the air detullop ria gniretne eht.gnidliub
hsidewS gnidliusBnoitalugeR
htroNaciremA
detinUmodgniK
detinU modgniK tsop0991
gnidliuBsnoitalugeR
detinU modgniK tsop9791
gnidliuBsnoitalugeR
roirP ot detinUmodgniK
gnidliuBsnoitalugeR
Figure 1 nosirapmoC foria
egakael sdradnats rof,sgnillewd
seciffo dna lairtsudnisgnidliub
gnidliuB( secivreS,lanruoJ
rebmetpeS)7991
Figure 2 nA elpmaxefo
noitalitnev hguorht ria egakaelfo
a noitcurtsnoc gnitluser nia
lamreht ’tiucric-trohs‘
Background 3
Figure 3 citamehcS fo naf noitasirusserp :tnempiuqe eht nafsecudorp
a erusserp ecnereffid}LED{ P aP neewteb edisni erusserp( P ) dna
ni
er uesds(iesrtpuo P ) rof a emulov wolf etar foQ m 3 s 1- .
tuo
3.3 riA egakael :sretemarap ria
egakael xedni dna ria
permeability
There are two parameters that are currently used to
quantify the air leakage rate through the building
.epolevne esehT era derrefer ot saair leakage index dnaair
permeability.
htoB eht ria egakael xedni dna eht ria ytilibaemrep fo a
gnidliub era derusaem yb eht naf noitasirusserp.euqinhcet Figure 4 lacipyT naf noitasirusserp tnempiuqe rof gnitset,sgnillewd
yehT era yllausu detats ni smret:fo dellatsni ni ayawrood
Figure 5 :NAFERB s’ERBnaf
pressurisation system
4 Testing buildings for air leakage
Figure 6 riA egakael citsiretcarahc :evruc wolfria etar dettolptsniaga
erusserp ecnereffid
— eht emulov wolf rep ruoh m( 3 h -1 ) fo ria deilppus
to the space by the air-moving equipment, per
erauqs ertemm( 2 ) fo gnidliub epolevne aera rofa
deificeps lanretni ot lanretxe erusserp ecnereffidfo
05 :aP rof ,elpmaxe 01m 3 h -1 m -2 at 50 Pa.
The building envelope area is the boundary or barrier
separating the interior volume of the building from the
outside environment. It normally includes any surface
taht si a yradnuob neewteb eht denoitidnoc lanretniecaps
dna eht lanretxe.stnemnorivne Figure 8 elpmaxE fo yhpargomreht desu ot tceted ria egakaelhguorht
.sliated ehT rekrad saera era ylevitaler ,looc dna eht rethgil saeraera
ylevitaler .mraw )a( mraW ria noitartlifxe ta eht sevae .liated )b( dloCria
The difference between the two air leakage parameters
noitartlifni ta eht gniddalc/llaw.liated
stsisnoc ni eht eciohc fo gnidliub epolevne .aera ehT ria
egakael xedni seod ton edulcni eht dilos dnuorg roolf,aera
while the air permeability does include the solid ground
floor area. It is not possible to standardise on one air bordering the internal volume V (m 3 ) of the building
leakage parameter at present because: (a) the proposed rednu .tset sihT aera si nevig yb eht latot fo eht ,sllawpot
European Standard prEN 13829 and Part L of the floor ceiling (or underside of roof) depending on where
Building Regulations use air permeability; (b) the eht ria reirrab si ,dna ni laiceps secnatsmucric ees(,)woleb
historical database of air leakage rate values relates to the inclusion of the area of the lowest floor, with no
air leakage index. The choice of which air leakage snoitcuded rof snoititrap dna noisivid sllaw htiw tnecajda
retemarap ot esu si erofereht tnedneped nopu eht txetnoc sgnidliub ro dehcatta.segarag
fo sti.esu
The area of the lowest floor area is included in the
3.3.1 riA egakael xedni envelope area when it is not ground supported. In this
case there is the potential for air leakage through it.
roF eht retemarapair leakage index eht gnidliubepolevne selpmaxE fo siht era a dednepsus rebmit dnuorg roolf nia
,aeraS m( 2 ,) si denifed sa eht lanretni ecafrus aera foeht gnillewd dna a rac krap htaeneb a eciffo .gnidliub ehTaera
fo detroppus-dnuorg etercnoc sroolf si ton dedulcni ni eht
external facade, and is calculated from the dimensions
epolevne .aera tnemesaB etercnoc sllaw era deifissalc eht
emas sa detroppus-dnuorg sroolf dna era ton dedulcni ni
eht epolevne.aera
The airtightness of dwellings has in the past been
desserpxe sa ria egakael etar ni ria segnahc rep ruoh,)HCA(
.e.i emulov wolf etarm( 3 h -1 ) ta 05 aP ecnerefer erusserp
difference per cubic metre (m 3 ) of building volume
( Q / .V) gnisserpxE ria egakael fo sgnillewd sa riaegakael
50
rates allows its air infiltration rate to be predicted using
eht ht02/1 elur ees( noitces.)6
3.3.2 riAytilibaemrep
riA ytilibaemrep si eht ria egakael retemarap desu ni eht
provisional European Standard prEN 13829. It has also
been found advantageous to use it, for reasons
Figure 7 A ekoms licnep gnitacidni ria egakael hguorht a ykaelwodniw of simplicity, in air leakage standards for both non-
frame -domestic and domestic buildings under the regulatory