an introduction to part l 2010rwiumbraco-gb2.inforce.dk/media/147282/part_l_brief.pdf · an...

An introduction to Part L 2010

Straight talking solutions

October 2010

Contents

Section 1 – The Approved Document 03-07

• Introductiontochanges

• RoadtoZeroCarbon

• ImplementationandtransitionalPeriod

• SustainabilityRoadmap

• Documentstructure

• Responsibilityforcompliance

• TheoreticalbuildingperformancevsActualbuilding Performance

• SummaryofMainChangestoPartL(2010)

• U-ValueCompetency

• Influentialdesignprincipals

Section 2 – New Build Dwellings (ADL1A) 08-13

• NewDwellings

•Methodofcompliance-SAP2009 (adoptingthe“Flat”Approach)

• Newbuilddwelling:U-valueguide

•MainchangestoSAP2009 (NewBuildDwellings(ADL1A))

• NewDwellingCasestudies

• SolutionsthatmeetPARTL1A- withoutrenewableenergygeneration

• PartyWallBypass

• Reducingheatlossfrompartywalls

• AcousticSolutions

Section 3 – L2A – New Builds OTHER 14-15 than dwellings (ADL2A)

•Methodofcompliance

• AirPressuretesting

• NewBuildNonDwellingsU-valueGuide

• Improvedrainnoiseperformanceusing roofing solutions

Section 4 – Work on Existing Buildings 16-17Dwellings (ADL1B) & Non-dwellings (ADL2B)

• Scopeofworkscovered

• ElementalU-valuesforExtensionwork

• Upgradingretainedthermalelements &Refurbishinginexistingbuildings (Dwellings&Nondwellings)

Section 5 – New Build guide solutions 18-23

• ExternalwallconstructiontoachieveaU-value of 0.25 W/m2k

• RoofconstructiontoachieveU-valuesof0.16 or 0.13 W/m2k

•MinimisingColdBridging-Extensions&NewBuildings

• ExternalwallconstructiontoachieveU-values of 0.28 W/m2k

• RoofconstructiontoachieveU-values of 0.16 or 0.18 W/m2k

Section 6 – Insulating Pipes and Ducts 24-25

• ThePartLsecond-tierdocumentsforpipeandduct insulation

• Domesticheatingcomplianceguide

•Minimumprovision

• Non-domesticheating,coolingandventilationcompliance guide

• Pipeworkandductinsulation

Section 7 – BuidDesk Part L 2010 Solutions 26

Section 8 – About Rockwool 27

• Sustainability

• ContinuingProfessionalDevelopment(CPD)

• Technicalsupport

Straight talking solutions | 3

Section 1 – The Approved Document

Sec

tio

n 1

OneofthekeyfeaturesofPartL2010isadrivetoclose the gap between the performance anticipated atdesignstageandwhatisactuallyachieved.Thesenewmeasureswillassistindeliveringrealcarbonsavingswithoutcreatingobstaclesforhousebuildersduringtheeconomicrecovery.

Itisclearthenewamendmentswillstillenablebuildersanddesignerstoachievecompliancethroughtheefficiencyofthebuildingfabricalone,whilstatthesametimeensuringthatmoreefficient,air-tighthomesandotherbuildingsaresufficientlyventilated.ToensureadequatemeansofventilationisprovidedtheApprovedDocumentFhasalsobeenrevised,andwas implemented at the same time as Part L.

Road to Zero Carbon

ThenewpartLwillnotonlyassistincuttingCO2 emissionsbutalsoplayacrucialpartinachievinggovernmentszerocarbonpolicies.

Proposedgovernmenttimescalesforfuturechangestoenergyefficiencystandards• 2013>a44%reductioninCO2 emissions (CodeLevel4)• 2016>Zero-carbonhomes(CodeLevel6CFSH)• 2019>Zero-carbon(non-domesticbuildings)

TheUKisalsothefirstcountrytoconfirmlegislationtorequireallnewhomestobezerocarbonfrom2016,withall“otherbuildings”tomeetthestandardfrom2019.

Sustainability Road map

Implementation and transitional Period

ThenewPartLandF2010documentsbecameenforceableonthe1stOctober2010.ThenewApprovedDocumentsstillcontaintransitionalprovisionsthatallowbuildingworktobecompletedafterthisdatewhichconformwiththerequirements ofPartsL&F2006.

Thistransitionalperiodwouldapplytofollowing:• Existingworkwhichhadalreadystartedbefore 1st October 2010 and where a building notice or full plans had been deposited with the Building ControlBody(BCB)• Newbuild,whereabuildingnoticeorfullplans hadbeendepositedwiththeBCBbefore1st October2010andworktohavestartedonsite before 1st October 2011.

Introduction to the changes

Thenewstandardsshoulddelivera25%reduction incarbonemissionsfromnewbuildingsrelativeto thestandardssetinthe2006PartL(equivalenttoCodeLevel3CodeforSustainablehomes).Thenewstandards will make new homes and non-dwellings moreenergyefficient,typicallysavinghouseholders£100ayearontheirheatingbillsandaround2milliontonnesofcarbonsavedeveryyearby2020.

2007 2008 2010 2013 2016 2019

Level 6mandatory

Part L Update

Level 4mandatory

Part L Update

Level 3mandatoryVoluntary

Assessmentmandatory

Code for Sustainable buildings

Level 6mandatory

Level 4mandatory

Level 3mandatory

Public Sector: Codeforsustainablehomes

Private Sector: Codeforsustainablehomes

4 | AnintroductiontoPartL2010

Document structure

Aswiththeprevious2006document,thenew PartL2010ispublishedin4parts.

Dwellings – L1 will be sub-divided into:• L1A:NewDwellings(methodofcompliance SAP2009)• L1B:WorkOnExistingDwellings(complianceachievedbytheelementapproach)

ADwellingmeansaselfcontainedunitsuchas ahouseorflatdesignedtoaccommodateasinglehouseholdandmustmeettherequirementsofADL1

Roomsforresidentialpurposes(suchasnursinghomes,residentialhomes,hostels,hotelsetc)arenotdwellingsandmustmeettherequirementsofADL2

Non-dwellings – L2 will be sub-divided into:• L2A:NewBuildings–OtherThanDwellings(methodofcomplianceNCM/SBEM2010)• L2B:WorkOnExistingBuildings–OtherThanDwellings(complianceachievedbytheelementapproach)

Responsibility for Compliance

Currentlyagreatdealofresponsibilityisplaceduponthedeveloperstoensurecomplianceismetwhichoften results in under compliance with the Building Regulations.ForBuildingControltoproperlyenforcethechanges,amorerobustsystemofbuildingassessment and performance checking is now being implemented

Itisimportanttorememberthattheperson(e.g.designer,builder,installer)carryingoutbuilding workhasaresponsibilitytoensurethattheworkcomplieswithBuildingRegulationrequirements. Thebuildingowneralsohasaresponsibilityforensuringcomplianceandcouldbeservedwithanenforcement notice in cases of non-compliance.


Sec

tio

n 1

Theoretical building performance vs Actual building Performance

OneofthekeyfeaturesofthenewPartL2010amendmentisadrivetoclosethegapbetweentheperformanceanticipatedatdesignstageandwhatisactuallyachieved.

Thereisincreasingconcernthatcurrentenergyandcarbonperformancestandardsarenotbeingachievedinbuildings,asconstructed.Apartfromtheresultsofairpressuretests,whichsuggestnewbuildings,(andhomesespecially),havebecomemoreairtightovertime,thereisawiderproblemrelatingtobuildingsactuallyperformingmorepoorlythantheyshould.Evidenceavailablesuggeststhatforbuildingsbeingconstructedtothe2006regulations,emissionsmaybeintheregionof15%higherthantheregulatoryperformancelevel.(ResearchcarriedoutbyCLG).Thisisreferredtobygovernmentasthe‘performancegap’.Ifwearetoachievetruezerocarbonby2016itisvitalthatthisgapbeclosed.

New measures put in place to improve compliance on site

1) Clearer Guidance:Thenewdocumentisclearerthanpreviousversionsindistinguishingbetween‘Regulation’and‘Guidance’.Thisshouldhelpdevelopersbetterunderstandwhatisrequiredofthemandgivebuildingcontrolclearerguidanceonhowtocheck for compliance.

2) Design Submissions:Therequirementtoproducea‘designsubmission’aswellasan‘asbuiltsubmission’,includingacomparisonofspecifications,willhopefullybringmorestandardisationandrigourtothecompliancechecks.ThiswouldinvolvedevelopersprovidingBuildingControlBodies(BCBs)with a design-stage submission containing not justtheSAPcalculationbutalsothecomponentspecificationswhichthedeveloperisgoingtousetodeliverthisresult.ThisKeyfeatureslistprovidedwiththe design stage submission will help to prioritise on siteinspections.(ThepersonthatpreparestheSAPcalculation would be responsible for checking that the proposed component specification is consistent withtheclaimedenergyperformance.).ArevisedSAPcalculationmustbesubmittedifthereareanychangestotheoriginalspecificationi.einsulationtypeorthickness,boilertype,windowsetcthen.

BCBsshouldreceivemoredetailedandaccurateinformationatthedesignstage,tostrengthentheabilitytoenforcethenecessaryRegulations.Thiswouldprovideclaritytodevelopersandarchitectsatthisvitalstageintheconstructionprocess.ByprovidingBCBswithmorerobustinformationaspartoftheBuildingRegulationssubmission,theywillbemoreabletocheckcomplianceonsitevisits,andtherefore,itismorelikelythatthefinishedpropertywillmirrorthe‘asdesigned’specification.Itwillstrengthentheirpositionandenablethemtoenforceandimproveon some of the poorer construction standards.

WithprofessionalenergyassessorsworkingintandemwithBCBstheconsumercanhavefullconfidence in both the finished building and the EnergyPerformanceCertificate.

3) Reducing Thermal bridging/Accredited Construction Details scheme:AmongstothermeasuresthataddresstheneedtoreduceCO

2

emissions,thatofhavingbetterinsulatedbuildingsrequiresmoresophisticatedmethodssuchasnumerical modelling to calculate the heat loss caused bythermalbridgingatwall,roofandfloorjunctionsand around openings.

InPartL2006,itwasacceptabletoassumeaneffectiveU-value(theyvalue)of0.08W/m2Kifaccreditedconstructiondetailshavebeenused. ThiswillnotbepossiblewithPartL2010.Instead,thelengthofeachjunctionwillneedtobemeasured,multipliedbytheappropriatepsivaluesandaddeduptoproducetheyvalue.ThepsivaluescaneitherbevaluesalreadysuppliedintheSAP2009documentorsuppliedbytherelevantapprovedgovernmentaccreditedconstructiondetailscheme.(0.04isthelikelyfiguretomeetcomplianceandstandarddetailsarebeingderivedbyBRE)

WiththeAccreditedConstructionschemedeveloperswouldberequiredtoregistertheiruseofaccrediteddetailsinordertoreceiveauniquereferencenumberwhichtheycouldinputintoSAP.Theoperatorsoftheschemewouldcarryoutrandomspotchecksonasampleofdevelopmentstoensurethattheaccrediteddetailswerebeingusedinpractice.(SimilartocurrentrequirementsforPartERobustdetails).

ConventionsforCalculatingLinearthermaltransmittanceandTemperatureFactors(BR497): Thisguidegivestheconventionsthatshouldbefollowedbynumericalmodellerstoproduceconsistent,reproducibleresults.ForBuildingRegulationpurposestwokeymodellingoutputs,temperaturefactorandlinearthermaltransmittance,areidentified.Thesekeyoutputswillenabledesignerstoconfirmtheadequacyofparticularjunctiondetailsandhelpwiththedevelopmentofnovelsolutionstoimprovethethermalperformanceofjunctions.

4) Developer confirms as-built conforms to design submission:ThiswouldinvolvedevelopersprovidingBCBswithanadditionalas–builtsubmissionwhichwillthenrequireanadditional“asbuilt“SAP/EnergyCertificate.Thenotionof‘confidencefactors’shouldstarttorewardthosedeveloperswhoadoptgoodqualitycontrolproceduresbothindesignandonsite.


‘Design’ submissions are now part of the Regulation AdesignstagecalculationandspecificationlistsubmissiontoBuildingControlBodieswillbeamandatoryrequirementbeforebuildingworktakesplace.PreviouslyonlytheAs-builtcalculationwas amandatoryrequirement.

Party walls–Plustheirassociatedthermalbypassheat losses will be included for the first time in the calculations.Youwillneedtoinsulateandsealyourpartywallcavityorusesolidwallsjusttomatchthenotional building.

Thermal bridges–‘AccreditedDetails’schemeaimedatensuringthatdevelopersonlyclaimenhancedbenefitsintheirSAPmodellingbyusingapprovedaccreditedconstructiondetailswhichhaveactuallybeenused(0.08foraccreditedconstructiondetailsisnolongeranoption)

Swimming Pools–NewIndoorswimmingpoolswillrequireaU-valueforthebasinwallsandfloorwhichshouldbenoworsethan0.25W/m²K

Air Permeability–Furtherimprovementsonairtightness.PartL2010nowrequiresdoublethenumberofpressureteststomeetcompliance.Generally avaluebetween5.0&7.0m3/(hm2)willgenerally needtobeachieved.Avalueof15.0m3/(hm2)can stillbeusedinsmalldevelopmentsbutwilltend torequireimprovingfurthertheperformanceofthermalenvelope.

Thermal Mass–Theheatcapacityoftheexternalandinternal building fabric will be used in the calculation ofTER&DERresults.Youwillnowhavetodefinetheinternalwalls,floorsandceilingsalongwithanypartywalls.Increasingtheeffectivethermalmassreducestheneedforheatingandcooling.Howevertherulesforcalculatingheatcapacitymeanthatitemssuchasinternaldrylining,thermalliningandlightweightconstructionswillreduceyoureffectivethermalmass.

Fabric limits–MaximumareaweightedU-valueshavebeenimprovedfromthe2006standards.TheareaweightedU-valuesshowninPartLaremaximumvaluesandunlikelytobelowenoughtocomplywithCO2emissionsrequirements.

Summary of Main Changes to Part L (2010)

U-Value Competency

RockwoolisoneofthefirstorganisationstobeapprovedunderanewvoluntaryU-valueandCondensationRiskCompetencySchemeintroducedbytheBritishBoardofAgrément(BBA)inassociationwiththeThermalInsulationManufacturersandSuppliersAssociation(TIMSA).

TheschemewasdesignedinresponsetoawidelyheldbeliefthatmanyU-valuecalculationssubmittedwereinaccurate.ThisassumptionhasbeensupportedbyrecentfindingsthatSAPassessorsarefrequentlygivenincorrect,incompleteorcontradictorydesigninformationconsequentlythereisastronglikelihoodthatthecarbonemissionscalculatedunderSAPmaynotbecorrect–andtheaffecteddesignsmaynotbecompliantwithBuilding Regulations.

Astudypublishedin2009bytheEnergyEfficiencyPartnershipforHomes(EEPH)andtheDepartmentofCommunitiesandLocalGovernment(CLG)reportedthat,in68%ofthedatasetsexamined,errorsoccurredininterpretingSAPconventionsforanumberofinputs;incorrectU-valueswerethemostfrequentsourceofinput error*.

ToaddressthisproblemRockwool,alongwithotherTIMSAmembershaveworkedwiththeBBAtodevelopacompetencyschemetopromoteandassistaccurate,objectiveandconsistentcalculationofU-valuesandcondensation risk within buildings.

RegistrationundertheSchemeprovidesreassurancetoaspecifieroruserthattheservicesorthedatabeingprovidedbyaschemememberhasbeensubjecttoarigorousindependentassessmentprocess.Theycanthereforebeassuredthatthisoutputisrepresentativeand reliable.

CalculationsprovidedbyqualifiedRockwoolemployees–andthoseprovidedbyRockwoolaswhole–arebackedupbytheBBACompetentPersonsLogo,whichsignalstoacustomerthatthedataprovidediscredible.RockwoolhavealsoestablishedaqualitycontrolsystemthatensuresthatallU-valueorcondensationriskcalculationsundertakenbythecompanyarecarriedoutdirectlybyafullyqualifiedcompetentperson,thuscomplyingwiththeScheme’srequirements.

TheuseofcorrectU-valuesisfundamentaltocompliancewithBuildingRegulations,determiningheatingandcooling costs for the building occupier and assessing environmentalperformance.

RockwoolandtheBBAencourageorganisationsthatrequireU-valueandCondensationriskcalculationsto obtainthisinformationfromsuitablyqualifiedcompanies. *EEPH/CLGResearchintoCompliancewithPartLoftheBuildingRegulationsforNewHomes–Phase2MainReportv0.4–30/4/09


Influential Design Principals

Alwaysstartwiththebuildingfabric.–Thefoundationofcomplianceshouldbethebuildingenvelope.

Buildingtype&configuration

BuildingEnvelopeU-values.

Glazingarea&orientation(solargain)

Thermalbridging(accreditedconstructiondetails)

Heating&hotwaterstorage:(fueltype,boiler &controls)

Ventilation(natural/mechanicalA/C)

Lighting(internal&external)

AirtightnessOneofthemaincausesofheatlossfrom homes is air leakage .

1 6

2 7

3 8

4

5

CompliancewiththeamendedApprovedDocumentisacomplex matter with a significant number of design considerations that need to be addressed.

FormostnewbuildingsitshouldbepossibletoachievetherequirementsofPartL2010withouttheneedtouserenewableenergytechnologies.

The primary factors that will determine compliance are shown in the illustration.

1

5

8

6

7

4

3

2


Section 2 – New Build Dwellings (ADL1A)

Inadditiontothisandtoavoidcompliancebeingdependantonemergingtechnologies(suchasrenewableenergysystems)thefabriclimitshavebeenstrengthenedtoensurethatbuildingelementsachieveahighlevelofthermalinsulationperformance.

• ThemaximumareaweightedU-valuesfor wallsimprovedfrom0.35to0.30,• ForRoofsfrom0.25to0.20,• ForGlazinganddoorsfrom2.2to2.0• Partywallsintroducedat0.20.

RememberthatthesearemaximumvaluesandsignificantlybetterfabricperformanceswillberequiredtoachievetheoverallTERCO2 targets.

New Dwellings

AswiththepreviousdocumentthenewPartL2010adopts a single compliance route based on the whole buildingenergyperformanceapproach.ThereforeelementalU-valuesalonewillnotachievetherequired25%improvementfactor.

Method of compliance – SAP 2009 (adopting the “Flat” Approach)

Undertheflatapproach,compliancewithPartL1Awillberequiredtobedemonstratedforeachindividualbuildingtypeinadevelopment.Thiswillneedtotakeintoaccountsize,orientationanddwellingtype(semi,endofterraceetc).

The2010TargetEmissionsRate(TER)wouldbe25%belowthe2006TER.Fornewdwellings,thereductioninCO2emissionsrelativetothenotionaldwelling(2002regulations)wouldincreasethecurrent20%bettermenttoapproximately40%.ThisisequivalenttoachievingCodeforSustainableHomesLevel3forCO2 emissions.

Influential factors: Inordertomeetcompliance,thefollowingconsiderationswillbeneedtobeaddressedatthedesignstage:• Buildingtypeandconfiguration• BuildingfabricU-values• Glazingandorientationofbuilding(solargain)• Thermalbridgingdetails• Spaceheatingandhotwater• Ventilationnaturalormechanical• Lighting• Airtightnessofthebuildingfabric


Sec

tio

n 2

There are a host of improvements to the SAP calculation methodology which will enable it to better reflect the performance of low energy buildings

1. A design stage calculation and specification list submission to Building Control Bodies will be a mandatory requirement before building work takes place. Previously only the As-built calculation was a mandatory requirement.

2. The TER and DER calculations will be calculated using SAP 2009 and will represent an additional 25% improvement on the previous regulations. Due to the significant number of changes to the calculation, do not automatically expect your previous Code Level 3 specifications or guidance to

achieve a Building Regulations pass under the new system without major revisions.

3. Party walls and their associated thermal bypass heat losses are will be included for the first time in the SAP calculations. You will need to insulate and seal your party wall cavity or use solid walls just to match the notional building. It will be impossible to improve on a U-value of zero which forms the basis of the Notional building. 4. The introduction of the Emission Factor Adjustment ‘EFA’ for heating and lighting will cause increased emissions for some fuels in the calculations. For example the EFA will effectively increases the CO2 emissions from grid electricity by 22.5%, bulk LPG by 4.7%, heating oil

by 3.4% and mains gas by 2% in the calculations Your choice of heating fuel has major implications on the CO2 emissions of the dwelling.

5. Thermal Mass The heat capacity of the external and internal building fabric will now be used in the calculation of TER & DER results. You will now have to define the internal walls, floors and ceilings along with any party walls, floors and ceilings. Increasing the effective thermal mass reduces the need for heating and cooling. However the rules for calculating heat capacity mean that items such as internal dry lining, thermal lining and lightweight constructions will reduce your effective thermal mass and therefore increase your CO2 emissions assuming U-values are unchanged.

6. You can now select up to 100% low energy lighting and take the corresponding savings in CO2 emissions. Previously you were restricted to a maximum of 30%, which was the same as that used in the notional building, regardless of the percentage of low energy lighting that you may have designed into your scheme.

7. Fabric limits have been strengthened, maximum area weighted U-values for walls improved from 0.35 to 0.30, Roofs from 0.25 to 0.2, Glazing and doors from 2.2 to 2.0 and Party walls introduced at 0.20. Remember that these are maximum values and are unlikely to be low enough to help you comply with the CO2 emissions.

Main changes to SAP 2009 (New build dwellings (ADL1A)

New build dwellings : U-value guide:

Duetothecomplexityofthedesignissueswithinthenewapproveddocumenttherewillnotbeasinglefabricsolutionforallnewbuilddwellingtypes.Designers and builders will find that compliance will onlybeachievedwitharangeofU-valuesasshownin the table below

Table1belowprovidesareasonableassessmentofthefabricU-valuesrequiredtodelivera25%reduction in carbon emissions for new build dwellings.

TheU-valuesshownhavebeendeterminedusingSAP2009softwarebasedonanumberofdifferentmodelhousetypedesigns.

In determining these U-values above other influential factors included the following:

• AirPermeability = 5–7m3/hr/m2

• Thermalbridging = 0.04W/m2K(50%improvementoncurrentdefaultallowance)• Partywall(semidetachedunits&flats) = Zero• WindowAv.U-value = 1.2to1.5W/m2K• Spaceheating = GasBoiler90%• Lowenergylighting = 100%• Ventilation = Natural

Fromatechnicalpointofview,2010compliancecanbeachievedbyimprovementstothebuildingfabricalone,withouttheneedforrenewabletechnology.

Element 2010 (25% CO2 reduction)

Walls0.27 to 0.24 W/m2 K Recommend 0.25 for design purposes

Pitched Roof insulation @ ceiling line 0.16 to 0.13 W/m2 K

Pitched Roof insulation @ rafter line 0.18 to 0.16 W/m2 K

Flat Roof or roof with integral insulation 0.18 to 0.16 W/m2 K

Ground Floors 0.20 to 0.15 W/m2 K

Party walls attached houses & flats Zero W/m2 K

Table 1 U-value guidelines for new dwellings


New Dwelling Case Studies

Element DetachedSemi-detached(Filled Party Wall)

Semi-detached(Non-filled Party Wall)

Mid terrace Mid floor flat

Floor area > 118m2 88m2 88m2 74m2 43m2

Roof u-value 0.13 0.16 0.16 0.16 N/A

Wall u-value 0.25 0.25 0.16 0.15 0.19

Party wall u-value N/A 0 0.20 0 0

Floor u-value 0.20 0.20 0.20 0.20 N/A

Window/doors u-value 1.5 1.5 1.5 1.5 1.5

Gas boiler efficiency 90% 90% 90% 90% N/A

Electric heat efficiency N/A N/A N/A N/A 100%

Secondary heating None None None None Electric

Design air permeability 5 5 5 5 5

Thermal bridging y-value 0.04 0.04 0.04 0.04 0.04

Hot water insulation (mm) 100 100 100 100 100

Ventilation system Natural Natural Natural Natural Natural

Low energy lighting 100% 100% 100% 100% 100%

Thermal mass parameter Low TF medium medium medium medium

Area EntriesRoof heat loss area 59 44 44 37 0

Wall heat loss area 147 108 108 64 43.34

Party wall area 0 43 43 77 25.68

Floor heat loss area 59 44 44 37 0

Opening area 20.25 18.76 18.76 14.58 12.08

Total external surface 265 196.4 196.4 138.0 43.34

Renewables no no no no no

Main ResultsTER 17.99 18.89 18.89 18.06 33.47

DER 17.84 18.72 18.80* 18.0 33.32

Pass/Fail Pass Pass Pass Pass Pass

Notes:• TheseassessmentshavebeencalculatedusingNHERSAP2010(preview1.4.14)toprovidepasseswithouttheneedforrenewables.• Thehousetypesshownaretobeusedasguidancepurposesandmayvarypendingspecificdesignconcepts.• VariationssuchastheThermalmassparameter,airpermeabilityandtheintroductionofrenewablesi.esolarwaterheating,willalsoimpactontheresultsshownabove.


Sec

tio

n 2Solutions that meet PART L1A – without

renewable energy generation.

Working on the principal that meeting the requirementsofPartLshouldstartwiththebuildingfabric,thetableonpage10showsthatitisquitepossibletoachievecompliancewithouttheneedforrenewableenergytechnologies.

TheexamplesshownclearlydemonstratethatU-valuesforthebuildingfabricwillvaryfromdwellingtypeacrossasite.InallcasesthebuildingfabricU-valuesrequiredaresignificantimprovementsonthose being built to meet Part L 2006 but still within theboundariesofpracticalaffordability.Obviouslyvariationonthecompliancemodelcanbeachievedbyusingdifferentelementssuchashigherefficiencyboilersforexample.

Section5(pages18to21)ofthisguideprovide aselectionofsometypicalconstructiondetails toachievetheU-Valuesshowninthistable.

IntheseexampleswehavetakensomestandardhousetypesandappliedthemtoNHERSAP2010withtheidentifieddesigncriteria.Inallcasescompliancehasbeenachievedapracticalandcosteffectivemanner.

The effect of Party wall Bypass

Thetwocompliancemodelsforthesemidetachedhouse show the huge impact that not filling the part cavitywallcanhave.Inthefirstwehaveassumed thatthepartywallisacavitywallwhichhasbeen filled with mineral wool and sealed at the edges. TheresultbeingthataU-Valueofjust0.25isrequiredfortheexternalwalls.Inthe2ndexamplethecavity is unfilled but the edges remain sealed thus assuming thedefaultU-valueof0.20forthepartywall.InthiscasecomplianceisachievedbymovingtheU-valueoftheexternalwallsto0.16–ahugeincreaseincostand wall thickness.

Pages12and13explaintheprincipalsthePartyWallThermalbypasseffectinmoredetail.

Thermal Mass

Inmostcaseswehaveassumedthatthebuildingsareofamediumthermalmasswhichisindicativeoftraditionalbrickandblockconstruction.Thedetachedhouseexampleusesalowthermalmassparameterwhichisindicativeoflightweightconstructionsuchastimber frame.

Air Tightness

ThelimitingvaluefortheairpermeabilityoftesteddwellingsinApprovedDocumentL1Aremains as 10 m3/(h.m2)atatestpressureof50pascals.HoweverSAP2009willassumeanairpermeability of7m3/(h.m2)inthenotionaldwellingandunlessotherenergysavingmeasuresareincorporatedintotheproposeddwelling,thenadesignairpermeabilityoflessthan7m3/(h.m2)mayberequired.Inourexamplesonpage10wehaveassumedanairtightnessof5whichwebelieveisachievableon apracticalbasisforbothmasonryandotherforms of construction.

Improvingtheairtightnessofthebuildingcanhave asignificanteffectonthefabricU-values.


Party Wall Bypass Effect.

Contrarytopreviousassumptions,partycavity-wallsarenotzeroheatlosswallsbecauseairflowinthecavityprovidesaheatlossmechanism.AmendmentstoPartL1A2010ofEnglandandWales’sBuildingRegulationsandSection6ofScotland’sBuildingstandards(domestic)haveforthefirsttimerecognisedthatwherepartycavity-wallsbetweenconnectedbuildingsareuntreated,considerableheatcanescapethroughthem.AkeyfeatureofSAP2009 isthatpartywallswithunfilledandunsealedcavitiesareassumedtohaveaU-valueof0.5W/m2K.

IncalculatingtheDERforaDwelling,thepartywallU-valuetobeassumedforthetypeofconstructionadopted is set out in table 2 below.

Party Wall Construction U-Value

Solid 0.00

Unfilled cavity with NO effective edge sealing 0.50

Unfilled cavity with effective edge sealing around all exposed edges and in line with insulation layers in abutting elements

0.20

Fully Filled cavity with effective edge sealing at all exposed edges and in line with insulation layers in abutting elements

0.00

Table 2

In applying the U-values in Table 2 it is important that where edge sealing is adopted, either on its own or in conjunction with a fully filled cavity, the sealing is effective in restricting air flow and is aligned with the thermal envelope.

Although effective sealing may be part of a cavity barrier, which is provided in order to comply with Part B (Fire), a cavity barrier on its own may not be effective in restricting airflow.

In order to claim a reduced U-value (0.2 or 0.0) it will be necessary to demonstrate that the design adopted is likely to be robust under normal site conditions.

Loft Space House A

Loft Space House B

Roof TilesRoof Tiles

Loft Insulation

Intermediate Floor

Party Wall

Cold External Air Infiltrating into Party Wall Cavity

Ground Floor Slab

Loft Insulation

Intermediate Floor

Ground Floor Slab

First FloorHouse A

First Floor House B

Ground FloorHouse A

Ground Floor House B

How it occurs

Whereoutsideairisabletoflowintothepartywallcavityacoldzoneiscreatedwhichresultsinheatfluxthroughthewallsectionsoneitherside.Theextentofwhichwilldependonexternalconditionssuch as wind and temperatures which create a ventilationstackeffectcausedbythewarmedairrisinginthecavitytobereplacedbycoolerairdrawninfromoutside.Theseairmovementscanbesignificantand,ifnostepsaretakentorestrictflows,theresultingheatlossescanbelarge.

AkeyfeatureofSAP2009isthatpartywallswithunfilledandunsealedcavitiesareassumedtohaveaUvalueof0.5W/m2K.ThenotionaldwellingusedincalculatingtheTERassumesaU-valueforcavitypartywallsofZERO(0.0W/m2K)

Acoustic Solutions

Withitscombinedthermalandacousticproperties,mineralwoolinsulation,suchasRockwool,hasbeenproventobeaneffectivemeansofmeetingthisnewchallenge.Recentfieldtrailshaveproventhatmasonrycavitiesfullyfilledwithblownmineralwool

insulation,notonlyhelpstoeliminatetheheatlossbutalso meets the Robust Details acoustic performance. Whenconsideringfullyfillingthepartycavity-walltheoverallmethodofconstructionwillinfluencethechoice of solution.

Further details along with comprehensive design advice can be found in the MIMA design guide: Preventing Thermal Bypasses in Party Separating Walls which can be downloaded from the mima website www.partywallbypass.com

Figure.AMasonry with Render and Plasterboard on Dabs

Figure.BTimber Frame Without Sheathing

• Externalcavityflankingwall• Sleeved,flexible,cavitybarrier• Partywallcavity 75mm(min)fullyfilledwithinjectedRockwoolEnergySaver

• Partywall Block100mm(min)eachleaf,density1350to1600kg/m3

• Wallfinish Gypsum-basedboard(nominalmass 8 kg/m2)mountedondabsoncement:sandrender(nominal8mm)withscratchfinish,andtypicalmix1:1:6to1:1/2:4.Rendermixmustnotbestrongerthan background.

• Externalcavityflankingwall• Flexiblecavitybarriersfor

fire, acoustic and thermal performance

• Partywall Width240mm(min)betweeninner faces of wall linings. 60mm (min)spacingbetweenstuds(mustnotbebridgedbyanydiagonalbracing)

• Interstudabsorbentmaterial Rockwoolrollorbatts,density22 kg/m3 to 60 kg/m3 to the full stud depth

• Interframeabsorbentmaterial Rockwoolrollorbatts,density22 kg/m3to45kg/m3,tofullyfillthevoidbetweenframesandbein full contact with the interstud absorbentmaterial.Itisimportantto site check the actual spacing between the frames and adjust the interframe absorbent material thicknessaccordingly

• Walllining


Sec

tio

n 2Reducing heat loss from party walls

Theheatlosscanbereducedbymeasuresthatrestrictairmovementthroughthecavity,bymeansoffullyfillingthecavitywithmineralwoolandbyprovidingeffectiveedgesealingaroundtheperimeterwalls.Theextenttowhichheatlosscanbereducedwill be dependent on the detailed design and the qualityofconstruction.

Theillustrationsbelow(figAandB)showthecurrentsolutionsdevelopedtoachieveazeroU-valueinthepartycavitywall.

Formasonrypartycavity-wallstheuseofblownmineralwoolinsulation,withamaximumdensityof40kg/m3hasbeenshownbysitetrialstoeliminateheatlossthroughthewallwithoutadverselyaffectingits acoustic insulation performance.

Forlightweightframedconstructionssuchastimberframe,thepreferredsolutionfortheindustrywillbetouselightweightfullfillslaborrollinsulation“builtin”asthewallconstructionproceeds.(Discussionsarecurrentlyongoingwithtimberframesystemholderstodeveloptestingprogrammes.)

TheintroductionofrequirementstoeliminatethePartyWallBypassEffectsupportsthedrivetodeliver‘real-life’energyefficiency,closingthegapbetweendesignedandas-builtperformance.Rockwool,withMIMA,areactivelyinvolvedindevelopingboth“built-in”and“retrofit”Robust solutions to meet these new proposals.

Method of compliance

Newnon-domesticbuildings:willrequirean“aggregate”improvementof25%intheenergyefficiencystandardsusingSimplifiedBuildingEnergyModel(SBEM)2010.Thisapproachreflectsthefactthatitisrelativelystraightforwardinsomebuildingtypestoimprovetheenergyperformancebymorethan25percent,whilstinotherbuildingtypesa25percentimprovementbecomesmuchmoredifficult.

Forexample,awarehousethatismostlyroof-litwouldbe different from an office which is side-lit or a building withnoglazingsuchasacinema.Thebuildingswillbeinzonessomaycombinedifferentelementsoftheglazingdefinition.

TheTargetEmissionsRate[TER]willvarybasedonwhatfuelisusedsothatmostbuildingwillhavecomparableefficiencystandardsregardlessoffuelused.Therewillnolongerbeanimprovementfactor;thesoftwarewillgenerateaTERwhichthedesignermustequalorexceed.


New buildings “other than Dwellings”

Aswithnewdwellings,newbuildnondwellingsalsoadopt a single compliance route based on the whole buildingenergyperformanceapproach

Air Pressure testing.

Allbuildingsmustnowbepressuretested,otherthanbuildings less than 500m2.ThelimitingvaluefortheairpermeabilityofbuildingsinApprovedDocumentL2Aremainsas10m3/(h.m2)atatestpressureof50pascals.However,theNationalCalculationMethodologywillassumeanairpermeabilityof5m3/(h.m2)inthenotionalbuildingandunlessotherenergysavingmeasuredareincorporatedintotheproposedbuilding,thenadesignairpermeabilityoflessthan 5 m3/(h.m2)mayberequired.

Section 3 – New Buildings OTHER than dwellings (ADL2A)

Duetothere-developmentoftheSBEMcalculationsoftware,atthetimeofgoingtoprint,ithasnotbeenpossibletoprovideclearsolutionstomeetingtherequirementsofPartL2A.Wewillpublishmoredetailsonourwebsiteinduecourse.ForfurtherdetailspleasecontacteitherRockwoolTechnicalserviceson08712221780


Element 2010 25%

Walls 0.25 to 0.24 W/m2 K

Roofs 0.20 to 0.16 W/m2 K

Ground Floors 0.22 to 0.20 W/m2 K

Table 3*

Sec

tio

n 3

In determining these U-values above other influential factors included the following:

• Windows&doors=U=1.8>1.5• Airpermeability=5m3/hr/m2

• Gasboilerefficiency=90%• Centralmechventilation=1.80• Multi-burnerradiantsystem=86%

*TablebasedonDraftCLGModellingSoftware

Section 3 – New Buildings OTHER than dwellings (ADL2A)

New Build Non Dwellings: U-value Guide

Thereisnosinglesolutionwhichcanbeappliedtoallbuildings.Constructionspecificationswillvarydepending on a wide range of criteria including the buildingtype.ItshouldbenotedthatnaturallightingandartificiallightingcanhaveanimpactontheoverallbuildingfabricU-values.

Table3providesindicativeU-valuesfornondomesticbuildingswhichhavebeenbaseddraftCLGmodellingusinggasheatingandthe“aggregate”25%approach.

IfabuildingfailsitsSBEMBER–TERcheck,themostlikelycausesinorderofprobabilityarelighting,heating,auxiliaryenergyandhotwater.

• testedsolutionstomeetallBB93requirements• easytouseBRERainNoisecalculatorhelpsyou

find the solution for each classroom• BREtestreportsavailableonrequest• canalsobeusedtomeetthermal,fire-stopping,lightreflectionandsustainabilityrequirements

• theadditionofaRockfonceilingsystemwillfurtherenhance the acoustic performance of the roof

Often thermal insulation materials can be used tomeetmorethanthethermalrequirementsoftheBuildingRegulations.Forexample,raincancauseunacceptablelevelsofbackgroundnoiseduringclass,seriouslyimpairinglearningandconcentration.Theproblemisparticularlyacutewithlightweightroofingcommonlyusedonschoolbuildings.TheissuehasbeenrecognisedinBB93,as well as other best practice codes and guidelines.

Rockwoolinsulatedroofs,canhelpsatisfytherelevantcriteriaforrainnoiseresistance,reverberationtimeandspeechintelligibility.

Improve rain noise performance using Rockwool roofing solutions

Try Rockwool’s rain noise calculator at

www.rockwool.co.uk/education


Section 4

Work on Existing Buildings Dwellings (ADL1B) & Non-dwellings (ADL2B)

Scope of works covered:

• Extensions• MaterialChangeofuse&Changeofenergystatus.• Workoncontrolledfittings&Services.• Renovationwork

Overview of Works for Extensions, Renovation & Repair work

CompliancewiththenewPartLwillberequiredwhen peopleelecttocarryoutworktoexistingbuildingsincludingextensionsandconversions,fabricrenovations,replacementwindowsandboilers

Aswithnewbuild,thereisageneralraisinginbuildingstandardsforexistingbuildingswithmorefocussedguidanceforthermalelements,replacementfittings,andheatingsystems.

However,unlikenewbuild,compliancecanstillbeachievedbyusinganelementalU–valueapproach asshowninthetablesbelow(forgreaterflexibility aSAP/SBEMmayalsobeused).

Elemental U-values for Extension work.

Reasonableprovisionfornewlyconstructedthermalelementssuchasthoseconstructedaspartof anextensionwouldbetomeetthestandardssetoutinTable4below(Thesealsoapplytoexisting nondomesticbuildings)

Element 2010 Standards 2006 Standard

Wall 0.28 W/m2 K 0.30 W/m2 K

Pitched Roof insulation @ ceiling line 0.16 W/m2 K 0.20 W/m2 K

Pitched Roof insulation @ rafter line 0.18 W/m2 K 0.20 W/m2 K

Flat Roof or roof with integral insulation 0.18 W/m2 K 0.20 W/m2 K

Floors 1 0.22 W/m2 K 0.22 W/m2 K

Swimming Pool basins 0.25 W/m2 K N/A

Alesserprovisionmaybeappropriatewheremeetingsuchastandardwouldcreatesignificantproblemsinrelationtoadjoiningfloorlevels.ThefloorU-valuefortheextensioncanbecalculatedusingthep/aofthewholeenlargedbuilding.

For Large non–domestic extensions L2B :wherefloorareaoftheextensionisgreaterthan100m2 and25%ofexistingfloorarea:TreatasnewbuildusingSBEMmethodology

Table 4 SummaryofnewfabricU–valuesfornewthermalelements

WindowsFormostexistingbuildings,thestandardfornewandreplacementwindows,isnowexpressedasaWindowEnergyRatingratherthanaU-value,withthestandardbeingraisedbytwogradingbands(from“E”to“C”).TypicallyUof1.6W/m2Kfordwellingscomparedto2.0W/m2Ktoday.

PleaserefertotablestandardsforwindowsanddoorsforexistingdwellingsandnondwellingsinPartL1B and L2B


Sec

tio

n 4Upgrading retained thermal elements & Refurbishment in existing buildings

(Dwellings & Non dwellings)

This Applies to following work:• Materialalterations• Whereexistingelementbecomespartofthethermalenvelopewherepreviouslyitwasnot.(Changeofenergystatus)• Renovation/refurbishmentofthermalelements

Renovation work in relation to thermal elements.Renovationinrelationtoathermalelementmeanstheprocessofstrippingdowntheelementtoexposethebasicstructuralcomponents(brick,timber/metalframe,joists,raftersetc.)andthenrebuildingtoachieveallthenecessaryperformancerequirements.

Renovationonlyapplieswheretheareatoberefurbished is greater than one of the following limits (smallerproportionsbeingregardedasrepairs):a)50%ofthesurfaceoftheindividualelement;orb)25%ofthetotalbuildingenvelope

Element (a) Threshold U- value (b) Improved U- value

Wall (cavity blown)2 0.70 W/m2 K 0.55 W/m2 K

Wall (externally or internally insulated) 3 0.70 W/m2 K0.30 W/m2 K(was 0.35 in ADL 2006)

Pitched Roof insulation @ ceiling line 0.35 W/m2 K 0.16 W/m2 K

Pitched Roof insulation between rafters 6 0.35 W/m2 K0.18 W/m2 K(was 0.20 in ADL 2006)

Flat Roof or roof with integral insulation 7 0.35 W/m2 K0.18 W/m2 K(was 0.25 in ADL 2006)

Floors 4, 5 0.22 W/m2 K 0.25 W/m2 K

Table 5 Upgradingretainedthermalelements&Refurbishment

1 Roof includes the roof parts of dormer windows and wall includes walls of dormers

2 thisappliesonlyinthecaseofawallsuitableforinstallationofcavityinsulation.Wherethisisnotthecasethenitshouldbetreatedas‘wall’-externalorinternalinsulation.

3 Alesserprovisionmaybeappropriatewheremeetingsuchstandardswouldresultinareductionofmorethan5%intheinternalfloorareaoftheroomboundedbythewall

4 Alesserprovisionmaybeappropriatewheremeetingsuchastandardwouldcreatesignificantproblemsinrelationtoadjoiningfloorlevels.

5 TheU-valueofthefloorofanextensioncanbecalculatedusingthep/aof the whole enlarged building.

6 Alesserprovisionmaybeappropriatewheremeetingsuchstandardswouldcreatelimitationsonheadroom.Insuchcasesthedepthoftheinsulationplusanyrequiredairgap,shouldbeatleastthedepthoftheraftersandthermalperformanceofchoseninsulantsuchastoachievethebestpracticalU-value.

7 Alesserprovisionmaybeappropriateifthereareparticularproblemsassociatedwiththeloadbearingcapacityoftheframeorupstandheight.

Notes relating to Renovation Work and table 3 aboveWhereathermalelementissubjecttoarenovation,theperformanceofthewholeelementshouldbeimprovedtoachieveorbettertherelevantU-valuesetoutincolumn(b)ofTable3.IfachievementoftherelevantU-valuesetoutincolumn(b)ofTable3isnottechnicallyorfunctionallyfeasibleorwouldnotachieveasimplepaybackof15yearsorlesstheelementshouldbeupgradedtothebeststandardthatistechnicallyandfunctionallyfeasible.(GuidanceonthisapproachisgiveninAppendixA.tableA1ofADL1B&L2B))


Section 5 – New Build guide solutions

External wall construction toachieveaU-valueof0.25W/m2k

Masonry cavity External Walls: • 102mmFacebrick,:• 110mmRockwool“Cavity”fullfillbatts,• 100mmAircreteblock(Lambda0.15)• Plasterboardondabfinish. (BuildtypeDomestic&NonDomestic)

Masonry cavity External Walls:• Renderon100mmmediumdenseblock• 100mmRockwool“Cavity”fullfillbatts,• 100mmAircreteblock(Lambda0.110)• Plasterboardondabfinish (BuildtypeDomestic&NonDomestic)

Masonry cavity External Walls – Built in

Cavity walls – Fully filled batts

Masonry cavity External Walls: .• 102mmFacebrick,:• 110mmRockwool“EnergSaverblown”

full fill• 100mmAircreteblock(Lambda0.110)• Plasterboardondabfinish. (BuildtypeDomestic&NonDomestic)

Masonry cavity External Walls:• Renderon100mmmediumdenseblock• 105mm Rockwool“EnergySaverblown”fullfill100mmAircreteblock(Lambda0.110)

• Plasterboardondabfinish (BuildtypeDomestic&NonDomestic)

Masonry cavity External Walls – Retrofit (blown insulation)

• RockShield render on 75mm RockShieldslab,

• 215mmsolidAircreteblock3.6N(0.150)• Plasterboardondabfinish (BuildtypeDomestic&NonDomestic)

• BrickShieldon 95mm Rockwool Facade Ultra

• 215mmsolidAircreteblock3.6N(0.150)• Plasterboardondabfinish (BuildtypeDomestic&NonDomestic)

Solid walls

CompliancewithallsectionsofPartL2010can beachievedwithavarietyofdifferentconstructions.Acrossthefollowingpagesweprovideasmallselection of building fabric solutions for both dwellings and non dwellings as well as new build andextensions.Furthersolutionsareavailablefromourbrochure:RockwoolGuidetoU-valueswhich can be downloaded from our website at www.rockwool.co.uk/partL.

AwiderrangeofconstructionscanbefoundinourGuidetoU-valuesavailablefromourwebsite www.rockwool.co.uk/partL


Sec

tio

n 5

Construction 3: Hybrid frame U–Value 0.25 (new build)• Cavitywallwith30mm Rockwool HP

partial fill on std Breather membrane on 9mmOSBon120mmsolidstudsfullyfilledwith 120mm Rockwool Flexi

• Std.VCL&12.5mmP/boardu-value 0.25

• Dittoaboveusing140mm flexi in 140mm stud U-Value =0.22

Construction 4: Solid 140 stud Single Timber framed wall 15% bridging U-value 0.25 (withtimbercladdingortilehanging)

• Cladding,Breathermembrane,9mmOSB140mm Rockwool Flexi between140mmsolid timber stud.

• HPDuPontAltguardVCL,25mmbattenedservicezone12.5mmplasterboard.

(BuildtypeDomestic):

Construction 1a: I stud 145 x 45 mm• 102mmFacebrick,Standardbreathermembrane9mmosb,145mm x 45 I stud

• 140mmFlexiinsulationfullyfillingstuds• StandardVCL&12.5plasterboard• U-value0.25 (DittoaboveusingTyvekRolflex breathermembrane)

• U-Value=0.22

Timber Constructions options using TIMBER I studs 8.3% bridging

Twin skin cladding systems – Roof & Wall

• U-valueexamplebased0.18:• Screedon100mmconcreteslabon135mm Rockwool

Rockfloor on dpm (Notethicknessbasedondetachedhouse12x8mwithP/A of0.420)insulationthicknesswillvarypendingfloorarea)into (BuildtypeDomestic&non-domestic):

Ground Floors

Construction 1: Solid 140mm stud 15% bridging• 102mmFacebrick,TyvekReflexHPbreathermembrane9mmosb,

• 140mmstdTimberframe*,140mmFlexiinsulationfullyfillingstuds.

• VCL&12.5plasterboard• u-value0.25

Construction 2: Solid stud with service zone• 102mmFacebrick,TyvekReflexHP

breather membrane • 120mm stdTimberframe*,120mm Flexi insulationfullyfillingstuds.AirguardHPVCL25mmbattenedservicevoid,.12.5plasterboard u-value 0.25

• Dittoaboveusing140mm flexi in 140mm stud to give U-Value =0.22

Constructions options using Solid timber studs 15% bridging

Roof• Twinskinmetalcladding)

u=0.16• 300-320mmRockwoolCladdingroll(un-faced)

(Buildtypenon-domestic):

Wall• Twinskinmetalcladding)

u=0.25• 180>200mmRockwoolCladdingroll(Foilfaced)

•Thicknessmayvarypendingsystemtype

(Buildtypenon-domestic):


Section 5 – New Build guide solutions

Roof construction toachieveU-valuesof 0.16 or 0.13 W/m2k

Pitched roofs horizontal insulation

Room in roof – based on U-value 0.16

• Singleplymembrane• 235mm(2layer)RockwoolHardrockDDonMetaldeck (Buildtypenon-domestic)

Flat roofs – based on U-value 0.16

Hybrid Flat roofs u=0.16 7.8% timber bridging

• Timberdeck• Singleplymembraneon105mmHardrockonbreathermembraneontimberdeck140mmRockwoolFlexibetweenjoists

• VCLandplasterboardfinish (Buildtypedomestic)

Hybrid Timber Flat roofs – based on U-value 0.16 (non vented)

• Raftersspaced@600ctrs (7.8%timberbridging)

• Tilesandbattens,,breathermembrane, 60mm Rockfall Overlayboardoverrafters

• 200mmRWFlexibetweenrafters,u=0.16standardVCL,.12.5mmp/boardfinish

• 80mmOverlaywith230mm(140+90mm) Flexiu=0.13(BuildtypeDomestic& non-domestic)

• Option1rolls:u=0.16270mmRockwoolRoll(1layerof100mmbetweenjoistsplus1Layer170mmRolllaidoverjoists

• Option1au=0.14:200mmRolloverjoists+100mm between

• Option1bu=0.13:220mmRolloverjoists+100mm between

• Option2blown:u=0.16270mmRockwoolRockPrime blown loft insulation

• Option2ablown:u=0.14 310mm Rockwool RockPrime blown loft insulation

• Option2bblown:u=0.13 330mm Rockwool RockPrime blown loft insulation

(BuildtypeDomestic&non-domestic)

Pitched roofs horizontal ceiling u=0.16 – 0.13 9% timber bridging

Room in roof: Insulation @ rafter line U=-0.16 + 0.13 Rockwool Rockfall Warm pitched roof Insulation between & over rafter


Sec

tio

n 5

Minimising Cold Bridging – Extensions & New build

Window & Door Reveals

RockReveal Masonry RockReveal Timber Frame

Rockclose (insulated dpc) Rockclose 20mm thick RW

AccreditedConstructionDetailsguidanceisavailabletoassisttheconstructionindustryinachievingtheperformancestandardsinADL.

Aroundopenings,suchaswindowsanddoors,AccreditedDetailsprovidetheminimumrequirementsarefor:

• Proprietrycloserwithminimumthermalresistance pathof0.45m²K/W.

• Rockwooloffertwoproducttypestoaddress theserequirements:Rockclose insulated dpc and RockReveal

•Both of these products will exceed this performance requirement advocated in accredited construction details

• E.g.20mmthickRockwoolinsultedDPCprovides athermalresistancepathof0.55m²K/Wand0.70m²K/W@25mmthick

Reducesthermalheatloss,condensation& mould growth

Minimising Cold Bridging at Window & Door Reveals

Rockwool Fire rated cavity closers

20mm thick Rockwool insulation

20mm thick Rockwool insulation

Tominimiseairleakage,useflexiblesealantaroundinternalandexternalwindow and door frames andsills.Ensurethatthevapourcontrollayerandplasterboard are returned intoreveal.

Tominimisecoldbridgingandtoprovidefireintegrityatdoorandwindowreveals,fitRockwoolTCBcavityarounddoorandwindowreveals


Section 5 – Extensions guide solutions

External wall construction toachieveaU-valueof0.28W/m2k

• 102mmFacebrick,:• 100mmRockwool“Cavity”fullfillbatts,• 100mmstd3.6NAircreteblock (Lambda0.150)

• LightPlasterfinish.(BuildtypeDomestic &non-domestic):

• Renderon100mmmediumdenseblock• 95mmRockwool“Cavity”fullfillbatts,• 100mmstd3.6NAircreteblock (Lambda0.150)

• LightPlasterfinish.(BuildtypeDomestic &non-domestic):

Masonry cavity External Walls:

RockShield render on• 75mmRockshieldslab,• 215mmsolidAircreteblock3.6N(0.150)• LightPlasterfinish(BuildtypeDomestic &nondomestic):

BrickShield on• 85mmRockwoolFacadeUltra• 285mmsolidAircreteblock3.6N(0.150)• LightPlasterfinish(BuildtypeDomestic &non-domestic):

Solid Walls

Single Timber framed wall

With timber cladding or tile hanging• Cladding,Breathermembrane,9mm

OSB 140mm Rockwool Flexibetween140mmtimberstud.• STDVCL,25mmbattenedservicezone12.5mmplasterboard.(BuildtypeDomestic):

• Screedon100mmconcreteslabon110mm Rockwool Rockfloor on dpm

• (Notethicknessbasedonextensionsizeapprox5mx4m)insulationthicknesswouldbereducediffloorareaof“whole“buildingtakeninto(BuildtypeDomestic &non-domestic):

Ground Floors U-value 0.22

Awiderrangeofconstructioncanbefound inourGuidetoU-valuesavailablefromour website www.rockwool.co.uk/partL


Sec

tio

n 5Roof construction toachieveU-valuesof0.16or0.18W/m2k

Pitched roofs horizontal ceiling u=0.16 9% timber bridging• Option1:270mmRockwoolRoll(1layerof100mmbetweenjoistsplus1Layer170mmRolllaidoverjoists

• Option2:270mmRockwoolRockPrimeblownloftinsulation (BuildtypeDomestic&non-domestic):

Room in roof: Insulation @ rafter line U= 0.18 Rockwool Rockfall Warm pitched roof Insulation between & over rafter• Raftersspaced@600ctrs(7.8timberbridging)• Tilesandbattens,,breathermembrane,70mm RockfallOverlayboardoverrafters,

• 140mmRWFlexibetweenrafters,Standardvcl&12.5mmplasterboard finish

(BuildtypeDomestic&non-domestic)

Pitched roofs horizontal Room in roof

Insulation between rafters only U= 0.18 7.8% timber bridging• Tilesandbattens,HPbreathermembrane,200mm(2x100)

Rockwool RWA45 (or 220mm Flexi)betweenrafters,Hpfoilvcl,• 25mmbattenedservicezone,&.plasterboardfinishtorafters.(BuildtypeDomestic):

Roof – Twin skin metal cladding u=0.18 • 260mmRockwoolCladdingroll(un-faced)(Buildtypenon-domestic):• Thicknessmayvarymarginallypendingcladdingsystemtype (Buildtypenon-domestic):Wall – Twin skin metal cladding) u=0.28• 150mmRockwoolCladdingroll(Foilfaced)(Buildtypenon-domestic):• Thicknessmayvarypendingsystemtype

Insulation between rafters Twin skin metal cladding – Roof & Wall

Flat roofs u=0.18• Singleplymembraneon210mm(2x105mm)• RockwoolHardrockDDonMetaldeck (Buildtypenon-domestic):

Hybrid Flat roofs u=0.18 7.8% timber bridging• Singleplymembraneon65mmHardrockonbreathermembraneontimberdeck140mmRockwoolFlexibetweenjoists

• VCLandplasterboardfinish. (Buildtypedomestic):

Flat roofs (Metal deck) Hybrid Timber Flat roofs


Section 6 – Insulating Pipes and Ducts

Theinsulationofpipesandductsisessential tominimiseheatlossesforheatedsystemsandheatgainsforcooledsystems.Forcooledsystems,itisalsoimportanttoensurethatthe riskofcondensationisadequatelycontrolled.ThenewApprovedDocumentsADL1A,ADL1B,ADL2AandADL2Brelyon‘second-tier’documentspublishedbyCLGtoprovidedetailedinformationontheminimumprovisionsnecessarytocomplywiththerequirementsoftheRegulations.

ADL1A and ADL1B – DwellingsThe‘DomesticBuildingServiceComplianceGuide(2010)providesguidanceonthemeansofcomplyingwithrequirementsforspaceheatingsystemsandhotwatersystemsinnewandexistingdomesticbuildings.

ADL2A and ADL2B – Buildings other than dwellingsThe‘Non-DomesticBuildingServiceComplianceGuide(2010)providesguidanceonthemeansofcomplyingwithrequirementsforspaceheatingsystems,hotwatersystemsandcooling&ventilationsystemsinnewandexistingnon-domesticbuildings.

The Part L second-tier documents for pipe and duct insulation

Domestic heating compliance guide

CompliancewithapproveddocumentsL1A: newdwellingsandL1B:existingdwellings

ApprovedDocumentsADL1AandADL1B(2010)relyon‘secondtier’documentstoprovidedetailedinformationontheminimumprovisionsnecessary tocomplywiththerequirementsoftheRegulations.

TheDomesticHeatingComplianceGuideisasecondtierdocumentprovidingguidanceonthemeansofcomplyingwiththerequirementsforspaceheatingsystemsandhotwatersystems.

Minimum provisions for insulation of pipes Theminimumprovisionsshownbelowfortheinsulation of pipes are repeated in the Domestic HeatingComplianceGuideforfueltypesandheatingsystemsasfollows;• Gas-firedprimaryandsecondaryspaceheating

and hot water• Oil-firedprimaryandsecondaryspaceheating

and hot water• Electricprimaryandsecondaryspaceheating

and hot water• Solid-fuelprimaryandsecondaryspaceheating

and hot water• Communityheating• Solarwaterheating

Minimum provision

Innewsystemspipesshould,inthefollowingcases,beinsulatedwithinsulationcomplyingwiththerequirementsoftheDomesticHeatingComplianceguide(inlinewiththemaximumpermissibleheatlossindicatedintheSupplementaryInformationcolumn),andlabelledaccordingly:• Primarycirculationpipesforheatingandhotwatercircuitsshouldbeinsulatedwherevertheypassoutsidetheheatedlivingspaceorthroughvoidswhichcommunicatewithandareventilatedfromunheated spaces

• Primarycirculationpipesfordomestichotwatercircuitsshouldbeinsulatedthroughouttheirlength,subjectonlytopracticalconstraintsimposedbytheneed to penetrate joists and other structural elements

• Allpipesconnectedtohotwaterstoragevessels,includingtheventpipe,shouldbeinsulatedforat least 1m from their points of connection to the cylinder(ortheyshouldbeinsulateduptothepointwheretheybecomeconcealed)

• Ifsecondarycirculationisused,allpipeskepthotbythatcirculationshouldbeinsulated

Forreplacementsystems,wheneveraboilerorhotwaterstoragevesselisreplacedinanexistingsystem,anypipes(inthesituationsabove)thatareexposedas part of the work or are otherwise accessible shouldbeinsulatedwithinsulationcomplyingwiththerequirementsoftheDomesticHeatingComplianceguide(inlinewiththemaximumpermissibleheatlossindicatedintheSupplementaryInformationcolumn),andlabelledaccordingly–ortosomelesserstandardwhere practical constraints dictate.


Sec

tio

n 6

Table 2: Maximum Permissible Heat Loss (W/m) (Thickness of Rockwool Rocklap H&V Pipe Section)

Pipe Outside Diameter (mm)

Hot Water1 Low Temp. Heating2

≤ 95°CMedium Temp Heating3

96°C – 120°CHigh Temp Heating4

121°C – 150°C

17.2 6.60 (25mm) 8.90(25mm) 13.34(25mm) 17.92(25mm)

21.3 7.13(25mm) 9.28(30mm) 13.56 (30mm) 18.32 (30mm)

26.9 7.83(30mm) 10.06 (35mm) 13.83 (40mm) 18.70(40mm)

33.7 8.62 (30mm) 11.07(35mm) 14.39(45mm) 19.02(50mm)

42.4 9.72(30mm) 12.30 (35mm) 15.66 (50mm) 19.25(60mm)

48.3 10.21 (35mm) 12.94(40mm) 16.67(50mm) 20.17(70mm)

60.3 11.57(35mm) 14.45(40mm) 18.25 (60mm) 21.96(70mm)

76.1 13.09(35mm) 16.35 (45mm) 20.42(60mm) 24.21(80mm)

88.9 14.58(35mm) 17.91(45mm) 22.09(60mm) 25.99(80mm)

114.3 17.20(40mm) 20.77(45mm) 25.31 (70mm) 29.32(80mm)

139.7 19.65(40mm) 23.71(50mm) 28.23 (70mm) 32.47(90mm)

168.3 22.31 (40mm) 26.89(50mm) 31.61 (70mm) 36.04(90mm)

219.1 27.52(40mm) 32.54(50mm) 37.66(70mm) 42.16(90mm)

273.0&above 32.40(40mm) 38.83 (50mm) 43.72(80mm) 48.48(100mm)

NOTES1,2,3,4Toensurecompliancewithmaximumpermissibleheatlosscriteria,proposedinsulationthicknesses shouldbecalculatedaccordingtoBSENISO12241usingstandardizedassumptions: 1Horizontalpipeat60°Cinstillairat15°C 2Horizontalpipeat75°Cinstillairat15°C 3Horizontalpipeat100°Cinstillairat15°C 4Horizontalpipeat125°Cinstillairat15°CDueto‘roundingup’tothenearestcommerciallyavailablethickness,thethermalperformancerequiredwillbe metorexceeded.

Maximum permissible heat loss (W/m) for direct hot water and heating pipes. Table41section11ofBuildingservicescomplianceguide(2010Edition).

Non-domestic heating, cooling and ventilation compliance guide

CompliancewithapproveddocumentsL2A:NewBuildingsotherthanDwellingsandL2B:ExistingBuildings other than Dwellings

Pipework and duct insulation

ApprovedDocumentsADL2AandADL2Brelyon‘second-tier’documentstoprovidedetailedinformationontheminimumprovisionsnecessary tocomplywiththerequirementsoftheRegulations.

The‘Non-Domesticisasecond-tierdocumentprovidingguidanceonthemeansofcomplyingwiththerequirementsforspaceheatingsystems,hotwatersystems,coolingandventilationsystems.

Section11oftheNon-domesticBuildingServicesComplianceguide2010outlinestheminimumprovisionsneededtocomplywithADL2AandADL2Bwheninsulatingpipesandductsservingspaceheating,hotwaterandcoolingsystemsinnew-buildandinexistingbuildings.

Theinsulationofpipesandductsisessentialtominimiseheatlossesforheatedsystemsandheatgainsforcooledsystems.Forcooledsystems,itisalso important to ensure that the risk of condensation isadequatelycontrolled.AlthoughnotwithinthescopeoftheNon-domestic,guidanceoncontrollingcondensationisalsoprovidedinAnintroductiontoPartL–insulatingpipesandducts.a directhotwaterpipesandlow,medium & high temperature heating pipes b cooledwatersupplypipesc heatedairducts,cooledairductsand dual-purpose heated & cooled air ductsd condensation control


Section 7 – BuildDesk Part L 2010 Solutions

BuildDeskisanindependentproviderofenergydesignsoftware,servicesandconsultancyinthefieldofenergyefficiency.OurproductsaredesignedtohelpArchitects,engineersandbuildingdesignersmeetandexceedtherequirementsofthenewApprovedBuildingRegulationPartL(2010)documents.

BuildDesk Software toolsOuruserfriendlysoftwaretoolsaredesignedto allowyoutoquicklycheckyourdesignproposals andgeneratesupportingreportsforBuildingControl.Oursoftwaretoolsinclude:

BuildDesk U OureasytouseU-valuecalculatorhelpsyoutobuildupyourownconstructionsandcheckthemin2D&3D.Withover500genericconstructionsandacomprehensivelistofconstructionmaterialstochoosefrom,youcanquicklyproduceaccurateU-valuecalculations.ItcomeswithanintegratedCondensationRiskanalysiscalculatorwhichhelpsyoutoassessmentyourconstructionsforinterstitialandsurfacecondensationrisk.Newforthelatest2010regulations,BuildDeskUnowcomescompletewithanautomaticHeatcapacitycalculationofyourconstructions.HeatcapacitiesarenowanimportantrequiredinthelatestSAP2009&SBEMcalculationswheretheyareusedtoestablishtheeffectivethermalmassofyourbuilding.

BuildDesk Carbon CheckerCarbonChecker,ouralternativetoiSBEM,isdesignedfornewandexistingnon-domesticbuildings.Thispowerfuldesigntoolallowsyoutodrawin,ortracethebuildinggeometryfromyourCADdrawingsandmakequickchangestothedesign.CarbonCheckerismuchmoreuserfriendlyandusefulwhencarryingoutrapidassessmentsofbuildingsforBuildingRegulations,fromdesignsubmissionstoas-built,includingthefinalEnergyPerformanceCertificate.

Alloursoftwareproductsareavailableforafreetrial.Justvisitthe‘oursoftware’sectionourwebsiteatwww.builddesk.co.uk.

BuildDesk Services & ConsultancyAsacomplementtooursoftwaretoolsweofferarangeofservicesfromcalculationassistanceincludingthermalbridginganalysis;tohands-onsoftwaretrainingcoursesandCPDaccreditedseminars.

More InformationTokeepuptodatewithBuildingRegulations,developmentsinsustainableconstructionandthelatest news on forthcoming BuildDesk products and servicesvisitusonlineatwww.builddesk.co.ukandregisterforourNewsletter.

BuildDesk–amemberoftheRockwoolGroup.


Section 8 – About Rockwool

Sustainability

Rockwoolreliesonnaturallyoccurringentrappedairforitsthermalproperties.IthasneverusedozonedepletingsubstancesorgaseswithahighGlobalWarming Potential in its manufacture according to TheEnvironmentalProtection(ControlsonOzone-DepletingSubstances)Regulations2002.

RockwoolLtdisincreasinglyinvolvedinrecyclingwasteRockwoolmaterialthatmaybegeneratedduringinstallationoratend-of-lifedisposal,andhasarecyclingschemethatisrecognisedbyWRAPandtheEnvironmentAgency.

Continuing Professional Development (CPD)

RockwoolpersonnelaretrainedtoprovideavarietyofCPDpresentationsonarangeofsubjectsincluding therecentchangestoPartLofthebuildingRegulations.PleasecontactourCustomerServicesdepartment on08712221780forfurtherdetails

Rockwool

Rockwoolistheworld’slargestproducerofstonewoolinsulation and the second largest insulation producer globally.ThegrouphasannualsalesofEuro1.5billionandemploysover7,800staffinmorethan30countries.Ithas22factoriesaroundtheworld.

Rockwoolinsulationiscreatedfromnaturallyoccurringvolcanicdiabaserockwiththeoresmeltedand spun into fibres to create a wide range of insulationmaterials,rangingfromloftinsulationrollstoimpact-resistantroofingboards.Itisalsobondedtoproduce high performance panels.

Rockwoolprovidesafour-in-oneinsulationsolution,providinghighgradethermalinsulation,noiseinsulation,non-combustibleandstrongenvironmentalcredentials. Rockwool insulation is one of few productsthatcansavemorethan100timestheenergyusedforitsmanufacture.Rockwoolinsulationisalsorecyclableandcanbere-smeltedandspuninto new stone wool insulation rolls and panels.

Technical Support

OurtechnicalteamcanprovideexpertpracticaladviceonRockwoolproductsandsolutions,including:

• technicalspecificssuchasU-valuecalculation,condensationriskandrainnoise• productselection• installationguidance• acousticinformation• passivefireprotection• meetingBuildingRegulations

PrintedonFSCpaper.Pleasereuseandrecyclethisdocument.

Digitallyprinted,inshortprintrunstominimisetheeffectontheenvironment.

AvailableasaPDFdocument.

Rockwool Limited

Pencoed Bridgend CF356NY

www.rockwool.co.uk©CopyrightRockwoolSeptember–2010

Contact us

Forallgeneralortechnicalqueriesplease contactusat:

Tel: 0871 222 1780 Email:[email protected] Web: www.rockwool.co.uk

ByPostto: Rockwool Limited Pencoed Bridgend CF356NY UK