Non - Residential New Build 4.2.3 Pitched Roofs - Rafter...

Non - Residential New Build4.2.3 Pitched Roofs - Rafter Level

August 2008: Issue 1

4.0Non-residential new build

Non-residential New Build

Sales 0844 800 0135 Technical Advisory Centre 01744 766666 www.knaufinsulation.co.uk

Introduction find online pageSolution optimiser and pathfinder 330Design considerations 334

Design Details 512

Pitched Roof - Rafter Level Contents

find online pageBetween rafters only(Crown Room in Roof Roll 37) Pr01 512

Between rafter only (Crown Rafter Roll 32) Pr02 514

Between engineered timber rafters Pr04 516

Between and below rafter with(Crown Rafter Roll 32 or 37 and PIR) Pr05 518

Between and below rafter (Crown RafterRoll 32 or 37 and Polyfoam Linerboard) Pr06 520

Between and below rafters withcounter battens Pr07 522

Between rafters with service duct below Pr08 524

Between rafters with Multifoil below Pr09 526

Between and above rafters (PolyfoamPitched Roofboard with Raftersqueeze) Pr10 528

Between and above rafters(Rocksilk Pitched Roof Slab) Pr11 530

Between, above and below rafter Pr12 532

Refurbishment detailsUpgrading ceiling level insulation/HR underlay Pr13 534

General details 536

Pitched roofs – rafter levelSolution optimiser and pathfinder

Sales 0844 800 0135 Technical Advisory Centre 01744 766666 www.knaufinsulation.co.uk330

4.2.3 Non-residential new build: Roofs

The thermal efficiency required by the Building Regulations,coupled with the desire to create interesting and attractiveinterior working spaces, can make the specification ofinsulation for this application a complex issue. Insulationplaced in the plane of the roof pitch creates a warm roof space.

Single layer sloping ceiling• Uses void in structure as insulation zone

• Semi rigid mineral wool products can be friction fitted with no special fixings, speeding up installation

• Simple installation from within sealed roof

• Utilises Euroclass A1 insulation throughout

• Using mineral wool insulation will significantly improve the acousticperformance of the roof

Rafter levelsloping ceiling• Use when low U-values are required

and internal lining would restrict head room in the room in roof

• Rafters are within the insulated envelope and kept warm, removing the risk of condensation forming on them

• Using mineral wool will significantly improve the acoustic performance of the roof

Double layer sloping ceiling• Systems can achieve low U-values even

with shallow rafters

• Minimises thermal bridging through timber rafters

• Systems with Low emissivity air layers provide service void

• Using mineral wool will significantly improve the acoustic performance of the roof

This option allows the designer to omit a flatceiling and use the space within the roof volumeas a functioning area of the property withoutsignificantly altering the building envelope.Where cables and piped services are to beinstalled within the heated envelope, theplasterboard lining may be battened out toprovide a suitable duct.

These types of construction require the installationof insulation at rafter level, following the pitch ofthe roof. Knauf Insulation products provide anumber of insulation options for this type ofconstruction, maximising both space and thermalefficiency.

Sales 0844 800 0135 Technical Advisory Centre 01744 766666 www.knaufinsulation.co.uk 331

4.2.3Non-residential new build: Roofs

Between and below rafters with counterbattensProduct*: Crown Room-in-Roof Roll 32 or 37 (2 layers)Description: Glasswool friction fitted between rafters, counter battens below infilled with glasswool Page No: 522

Pr07

Between rafters onlyProduct*: Rocksilk Flexible SlabDescription: Rock mineral wool friction fitted between rafters

Page No: 514

Between rafters onlyProduct*: Crown Room-in-Roof Roll 32 or 37Description: Glasswool friction fitted between rafters

Page No: 512Pr01

Pr02/3

Between engineered timber raftersProduct*: Crown Room-in-Roof Roll 32 or 37 Description: Glasswool friction fitted between engineered timber rafters

Page No: 516Pr04

Between and below rafterProduct*: Crown Rafter Roll 32 or Crown Room-in-Roof Roll 32 or 37 Description: Glasswool friction fitted between rafters, PIR fixed below rafters

Page No: 518

Between and below rafters with insulated plasterboardProducts*: Crown Room-in-Roof Roll 32 or 37, Polyfoam Liner BoardDescription: Glasswool friction fitted between rafters, insulated plasterboard fixed below rafters Page No: 520

Elemental U-value requirement

Pitched roof with insulation at rafter levelConstruction compatibility with Part L2A

Knauf Insulation solution U-values 0.23 0.22 0.21 0.20 0.19 0.18 0.17 0.16 0.15 0.130.14 0.12 0.110.26 0.25 0.24 0.10

KeyU-values achievable by constructions within this document.

* Recommended Knauf Insulation product(s). Other products may be applicable.

Find online. Visit www.knaufinsulation.co.uk and key in construction code to find the most up to date information on your chosen solution.

Pb01

Area weighted average max

U-value England and Wales

and Northern Ireland

Typical U-value for compliance

England and Wales and Northern Ireland

Pr05

Pr06

continued overleaf

Between rafters with MultifoilProducts*: Crown Rafter Roll 32 or 37, Thinsulex multifoil/service voidDescription: Glasswool friction fitted between rafters, Thinsulex Multifoiland counter battens belowPage No: 526

Between rafters with service voidProduct*: Crown Room in Roof Roll 32 or 37Description: Glasswool friction fitted between rafters, Low E VCL and counter battens creating service void

Page No: 524

Between and above raftersProducts*: Polyfoam Pitched Roofboard,Polyfoam RaftersqueezeDescription: XPS board over rafters, compressible XPS board friction fitted between rafters Page No: 528

Between and above raftersProducts*: Rocksilk Krimpact Pitched Roofboard, Crown Room in Roof Roll 32 or 37, or Crown Rafter Roll Description: Rigid rock mineral wool board over rafters, friction fitted glasswool between rafters Page No: 530

Pr11



Pitched roofs – rafter levelSolution optimiser and pathfinder

KeyU-values achievable by constructions within this document.

* Recommended Knauf Insulation product(s). Other products may be applicable.

Find online. Visit www.knaufinsulation.co.uk and key in construction code to find the most up to date information on your chosen solution.

Pb01

Elemental U-value requirement

Pitched roof with insulation at rafter levelConstruction compatibility with Part L2A

Knauf Insulation solution

Pr08

Pr09

Pr10

U-values 0.23 0.22 0.21 0.20 0.19 0.18 0.17 0.16 0.15 0.130.14 0.12 0.110.26 0.25 0.24 0.10

Area weighted average max

U-value England and Wales

and Northern Ireland

Typical U-value for

compliance England and

Wales and Northern Ireland

continued from overleaf



Pitched roofs – rafter levelInsulation at rafter level design

Utilising the loft area as a working spaceMany designers of commercial and publicbuildings (especially offices and schools) use theheight offered in the pitch of the roof to createlight, attractive interiors with high level slopingceilings which include light wells and roofwindows. The thermal efficiency required by theBuilding Regulations, coupled with the desire tocreate interesting and attractive interiors, canmake the specification of insulation for thisapplication a complex issue.

Pitched roofs – rafter levelInsulation at rafter level design



Rafter level insulationInsulation between the rafters can be designed intwo ways:

• ‘Breathing’ roof with LR underlay

• Ventilated design with HR underlay

Rafter level insulation with LR underlayWith this option, insulation fully fills the rafterspace without an airspace between the insulationand type LR underlay. Counterbattens are neededto ensure wind driven rain drains freely to thegutter.

The space created by the counterbattens allowsthe dispersion of any moisture that passesthrough the breather underlay. Where the roofcovering is very tight fitting, eaves ventilationabove the underlay is recommended.

A combined airtight/vapour control layer shouldbe placed on the warm side of the insulation. Thisnot only makes the ceiling convection tight, butalso restricts the amount of water vapour passing through the ceiling.

Where cables and piped services are to beinstalled, the plasterboard lining may be battenedout to provide a suitable servicesduct. The services should be routed on the warmside of the vapour control layer to avoid any puncturing.

Over rafter insulation with LR underlayInsulation over the rafters provides a completelyinsulated external envelope to the roofconstruction, and allows the maximum usablespace within the roof enclosure.

The insulation boards are laid across the rafters.It is important that there should be no gaps in theinsulation layer and no ventilation between theoutside and the attic space. A LR underlay mustbe provided to allow moisture vapour to diffusethrough the entire roof construction.

Counterbattens are fixed through the insulationboards and vapour permeable underlay into therafters. Where the over rafter insulation is over50mm thick, consideration should be given to thefixing of the counterbattens.

Further insulation is placed between the rafters toachieve the desired entire performance.If the insulation board over the rafters has a highvapour resistance, the use of mineral woolbetween the rafters is not recommended unlessthe designer is confident that an effective vapourcontrol layer can be provided to the underside ofthe rafters.

The rafters should be faced with 12.5mmplasterboard, or similar, to provide fireprotection.

Rafter level insulation with HR underlayWith this design, a 50mm ventilated airspace isrequired between the top of the insulation and thetiling underlay. Should the rafter depth beinsufficient to accommodate both the requiredthickness of insulation and the 50mm ventilatedairspace, an insulation/plasterboard laminate isrecommended. This has the added benefit ofminimising thermal bridging.

Ventilation openings should be provided at eachand every roof void at both low and high level.At the eaves, ventilation openings should beequivalent to a 25mm continuous gap. At theridge the ventilation opening should be theequivalent of a 5mm continuous gap each side ofthe ridge.

Care is needed where rooflights and dormerwindows interrupt the ventilation path. Ventilationto the outside must be provided at the top andbottom of each space between the rafters.

It is usual for the HR underlay to drape at least10mm between the rafters to avoid the need forcounterbattens.

A vapour control layer must be applied to thewarm side of the insulation.

Flanking sound

Rafter level insulation with LR underlay

The roof and wall insulation should be tightly butted with no gaps to avoid air leakage and thermal bridging

Ventilation space created by counter battensGaps between tiles and slates allow watervapour to escape (for tight fitting slates,eaves ventilation is recommended).

Snow and rain driven through tilingcan drain safely to gutter Vapour control layer to

underside of insulation

UV resistant eaves tray to dress into gutter

Continuous diffusion of moisture

Insect guard

Continuous diffusion of moisture

BS 5250 provides guidance for pitched roofswith two types of tiling underlay:

• Type HR (high water vapour resistance), such as traditional sarking felt

• Type LR (Low water vapour resistance – less than 0.25 MN s/g)



Roofs insulated at rafter level that adjoin masonryseparating walls between ‘rooms for residentialpurposes’ can act as a flanking path for soundtransmission between the rooms. Using glasswoolroof space insulation will restrict the passage ofsound from the roof space into the rooms below,reducing the effect of flanking soundtransmission. The excellent acoustic properties ofmineral wool are also beneficial at rafter level inreducing the noise from road traffic andairplanes as well as rainfall drumming on theroof.

The ceiling and dwarf walls should be lined withtwo layers of plasterboard with a combinedminimum mass of 16 kg/m2 . Normally thiswould be achieved using two layers of 12.5mmPlasterboard, but could also be achieved using a layer of 9.5mmplasterboard and a layer of 15mm plasterboard.

Warm roof construction details to restrict flankingtransmissions and external noise

Two layers of plasterboard to underside of rafters and to dwarf

stud walls

Section A-A

Flexible closer between junction of separating wall and roof

12.5mmplasterboard(minimum mass8kg/m2)

Section through roof

100mm mineral wool (density of 10 kg/m3)

design detail finderKnauf Insulation solutions for these types of construction can be found on pages 512-539

Pitched roofs – rafter levelBetween rafters only


6.1.2 Design details: Pitched roofs

Advantages Uses void in structure as insulation

zone

Semi-rigid mineral wool products can be friction fitted with no special fixings, speeding up installation

Simple installation from within sealed roof

Utilises Euroclass A1 insulation throughout

Using Crown Room-in-Roof Roll 37 will significantly improve the acoustic performance of the roof – reducing airborne noise

Crown Room-in-Roof Roll 37 canbe used along with an extra layer ofplasterboard to satisfy the requirementsof Robust Details to restrict flankingsound around separating walls

Low cost option

Long rolls with greater coverage per roll than other equivalent products

Knauf Breatheline

InstallationKnauf Breatheline is pulled taught and laiddirectly over the rafters. 50x32mm counterbattens are nailed into the rafters with minimumpenetration of 38mm into the rafter.Alternatively, helical fixings can be used with aminimum penetration of 35mm into the rafter.Tiling battens are nailed into the counterbattens. Finally, the roofing tiles or slates arefixed to the manufacturer’s recommendations.

Crown Room-in-Roof Roll 37 is simply frictionfitted to fully fill the space between the rafters,with all joints closed, and is normally fitted frombelow once the roof is weathertight.

The roof insulation should be cut to shape to linkwith the wall insulation to avoid a thermalbridge at the eaves.

IntroductionThe most satisfactory method of insulating atpitch level within a roof is when the requiredthermal performance can be achieved withinthe depth of the rafters. This is because it doesnot increase the depth of the roof build up,special fixings are not required and allinsulation work can be carried out from withinthe sealed roof space.

Typical constructionA pitched roof of timber rafters with tiles orslates on battens and counter battens on KnaufBreatheline. The space between the rafters isfully insulated with Crown Room-in-Roof Roll 37.

ProductsCrown Room-in-Roof Roll 37 is made from glass mineral wool and formed into rolls whichare dimensioned to fit tightly between rafters at600mm centres. The rolls are lightweight,flexible, resilient and non-combustible, and arefaced with a low emissivity vapour control layer.The facing is wider than the roll to overlap therafters to aid fixing, and create a vapourcontrol layer. Its manufacture has a very lowimpact on the environment and is classified asZero ODP and Zero GWP*

* Ecohomes and Code for Sustainable Homes classification

Robust DetailsIn order to comply with the Robust Detailsrequirements for masonry separating walls androof junctions, the complete ceiling area shouldcontain at least 100mm of mineral wool(10 kg/m3 min) between the rafters andinstalled so that it is flush with the soffit of therafters. Any dwarf walls which are adjacent tothe separating wall where there are rooms inthe roof should also contain at least 100mm ofmineral wool (10 kg/m3 min).

Knauf Breatheline

Crown Room-in-RoofRoll 37

Plasterboard lining

Counter battens

Vapour control layer

Pr01

513

6.1.2Design details: Pitched roofs


Typical specificationThe whole area of the pitched roof to beinsulated with Crown Room-in-Roof Roll37…mm thick, friction fitted between therafters. The insulation to be pushed over thewall plate at the eaves to link up with thewall insulation.

Alternatively, refer to NBS clauses: P10/140and 320

Typical section

Table 7: Typical U-values of roofs with insulation between rafters

Product Thickness U-values

(mm) (W/m2K)

Crown Room-in-Roof Roll 37 200 0.20

160 0.25Notes: Rafter sizes assumed to be 38mm wide at 600mm centres (6.3% bridging) and the same depth as the insulation. The U-values have been calculated in accordance with BS EN ISO 6946:1997.

PerformanceThermal performanceCrown Room-in-Roof Roll 37 has a thermalconductivity of 0.037 W/mK.

Table 7 gives U-values for typical constructionswith insulation between the rafters.

Fire performanceCrown Room-in-Roof Roll 37 is classified asEuroclass A1 to BS EN ISO 13501-1.

Vapour resistanceKnauf Breatheline has a vapour resistanceof 0.22 MNs/g.

Refurbishment of existing roofsThis is a valid solution for the refurbishment of an existing roof where the roof tiles and roof tile underlay are not being removed. In thesecircumstances a continuous 50mm gap must be maintained between the insulation and the roof tile underlay which is vented at theeaves and ridge.

The U-values achieved are as shown in Table 7.

Plasterboard lining

Counter battens

Knauf Breatheline


Crown Room-in-Roof Roll 37

Pitched roofs – rafter levelBetween rafters only



InstallationKnauf Breatheline is pulled taught and laiddirectly over the rafters. 50x32mm counterbattens are nailed into the rafters with minimumpenetration of 38mm into the rafter.Alternatively, helical fixings can be used with aminimum penetration of 35mm into the rafter.Tiling battens are nailed into the counterbattens. Finally, the roofing tiles or slates arefixed to the manufacturer’s recommendations.

Crown Rafter Roll 32 is simply friction fitted (inlayers if necessary) to fully fill the spacebetween the rafters. All layers should be closelybutt jointed, and are usually installed frombelow once the roof is weathertight.

If installed in layers, ensure joints arestaggered.

The roof insulation should be cut to shape to linkwith the wall insulation to avoid a thermalbridge at the eaves.

A continuous vapour control layer should befixed to the underside of the rafters with alljoints sealed.

IntroductionThe most satisfactory method of insulating atpitch level in a roof is when the requiredthermal performance can be achieved withinthe depth of the rafters. This is because it doesnot increase the depth of the roof build up,special fixings are not required and allinsulation work can be carried out from withinthe sealed roof space.

Typical constructionA pitched roof of timber rafters with tiles orslates on battens and counter battens on KnaufBreatheline. The space between the rafters isfully insulated with Crown Rafter Roll 32.

ProductsCrown Rafter Roll 32 is made from glassmineral wool and formed into rolls which arelightweight, flexible, resilient and non-combustible. Its manufacture has a very lowimpact on the environment and is classified asZero ODP and Zero GWP*

Knauf Breatheline is a breathable membranewith a polypropylene non-woven coating onboth sides – see also page 534.

Rocksilk Flexible Slab is a semi-rigid rockmineral wool slab. In this construction RocksilkFlexible Slab can be used as an alternative toCrown Rafter Roll 32. See Table 9.


Robust DetailsIn order to comply with the Robust Detailsrequirements for masonry separating walls androof junctions, the complete ceiling area shouldcontain at least 100mm of mineral wool(10 kg/m3 min) between the rafters andinstalled so that it is flush with the soffit of therafters. Any dwarf walls which are adjacent tothe separating wall where there are rooms inthe roof should also contain at least 100mm ofmineral wool (10 kg/m3 min).

Advantages Uses void in structure as insulation

zone

Mineral wool products can be frictionfitted with no special fixings, speeding up installation

Simple installation from within sealed roof

Utilises Euroclass A1 insulation throughout

Using Crown Rafter Roll 32 willsignificantly improve the acousticperformance of the roof – reducingairborne noise

Crown Rafter Roll 32 can be used alongwith an extra layer of plasterboard tosatisfy the requirements of Robust Detailsto restrict flanking sound aroundseparating walls.


Pr03Knauf Breatheline

Pr02

Knauf Breatheline

Crown Rafter Roll 32

Plasterboard lining

Counter battens


PerformanceThermal performanceCrown Rafter Roll 32 has a thermalconductivity of 0.032 W/mK.

Rocksilk Flexible Slab has a thermal conductivityof 0.035 or 0.037 W/mK.

Tables 8 and 9 give U-values for typicalconstructions with insulation between the rafters.

Fire performanceCrown Rafter Roll 32 and Rocksilk Flexible Slabare classified as Euroclass A1 to BS EN ISO 13501-1.

Vapour resistanceKnauf Breatheline has a vapour resistanceof 0.22 MNs/g.


The U-values achieved are as shown inTables 8 and 9.

515



Typical specificationThe whole area of the pitched roof to beinsulated with Crown Rafter Roll 32/RocksilkFlexible Slab*…mm thick, friction fittedbetween the rafters. The insulation to bepushed over the wall plate at the eaves tolink up with the wall insulation. (*Delete as appropriate)

Alternatively, refer to NBS clauses: P10/140and 320



(mm) (W/m2K)

Crown Rafter Roll 32 200 (100+100) 0.18

185 (100+85) 0.19

175 (100+75) 0.20

165 (100+65) 0.22Notes: Rafter sizes assumed to be 38mm wide at 600mm centres (6.3% bridging) and the same depth as the insulation. The U-values have been calculated in accordance with BS EN ISO 6946:1997.

Plasterboard lining

Counter battens

Knauf Breatheline


Crown Rafter Roll 32/Rocksilk Flexible Slab

Typical section



(mm) (W/m2K)

Rocksilk Flexible Slab 200 (2x100) 0.20

190 (100+90) 0.21

180 (2x90) 0.22

170 (100+70) 0.23

160 (90+70) 0.25

150 (90+60) 0.26Notes: Rafter sizes assumed to be 38mm wide at 600mm centres (6.3% bridging) and the same depth as the insulation. The U-values have been calculated in accordance with BS EN ISO 6946:1997.

Pr03

Pr02

Advantages Makes excellent use of the deep

rafter depth

Using Crown Rafter Roll 32 will significantly improve the acoustic performance of the roof restricting airborne noise

Crown Rafter Roll 32 can be used along with an extra layer of plasterboard to satisfy the requirements of Robust Details to restrict flanking sound around separating walls

Pitched roofs – rafter levelBetween engineered timber rafters



ProductsCrown Rafter Roll 32 is made from glassmineral wool and formed into rolls which arelightweight, flexible, resilient and non-combustible. Its manufacture has a very lowimpact on the environment and is classified asZero ODP and Zero GWP*



Typical constructionA pitched roof of engineered timber rafters withtiles or slates on battens. 8mm plywood sarkingfixed to the top of the rafters with KnaufBreatheline laid across the plywood. Insulatedwith Crown Rafter Roll 32 between the rafterssupported by plywood fixed to the upper edgeof the lower flange of the engineered timberrafter and lined internally with a vapour controllayer and plasterboard.

Install the vapour control layer to the lower faceof the plywood support pieces and across thelower edge of each engineered timber flangetaping all joints to ensure its integrity ismaintained. After first fix services have beeninstalled finish using standard dryliningtechniques.

If the insulation is fitted from below then theplywood sarking board, Knauf Breatheline,counter battens, tilling battens and slates or tilesare fixed as above. Friction fit Crown Rafter Roll32 (in layers if necessary) between the rafters.The insulation should be butt jointed andcontinuous with the wall insulation to avoidthermal bridging. Install the insulation supportpieces and fix the vapour control layer to thelower face of the plywood support pieces andacross the lower edge of each engineeredtimber flange taping all joints to ensure itsintegrity is maintained. After first fix serviceshave been installed finish using standarddrylining techniques.

InstallationThe insulation is fitted from above or belowonce the roof is watertight.

If fitting from above fix the ply wood supportpieces to the upper edge of the lower flange ofthe engineered timber rafter making sure thetimber fits tightly to the sides of the web of therafters. Friction fit Crown Rafter Roll 32 betweenthe web and upper flange of the engineeredtimber rafter to the full depth, in layers ifnecessary. The insulation should be but jointedand continuous with the wall insulation to avoidthermal bridging.

Fix the 8mm plywood sarking board to the topof the rafters. Knauf Breatheline is laid directlyover the plywood sarking board and 50x32mmcounter battens placed on top of the KnaufBreatheline directly above the rafters and nailedinto the rafters with minimum penetration of38mm into the rafter – alternatively, helicalfixings can be used with a minimum penetrationof 35mm into the rafter. Tiling battens arenailed into the counter battens and the roofingtiles or slates are fixed to the manufacturer’srecommendations.

Knauf Breatheline

Pr04

Knauf Breatheline


Plasterboard

Counter battens

8mm plywood support for insulation

8mm plywood sarking

517



Knauf Breatheline


Crown Rafter Roll 32between rafters

8mm ply sarking

Counter battens

Service void formed in depthof lower flange

12.5mm plasterboard

Typical specificationThe whole area of the pitched roof to beinsulated with Crown Rafter Roll 32, ofthickness ...... mm friction fitted between theengineered rafters. The width of theinsulation should be appropriate to thespacing of the rafters.

Staple a vapour control layer to theunderside of the rafters and seal all joints.

Nail 50x25mm timber battens to the raftersto form a service void. Nail foil backedplasterboard to the timber battens.

Alternatively, refer to NBSclauses.

Table 10: Typical U-values for roofs with Crown Rafter Roll 32 between engineered rafters

Insulation U-values (W/m2K)Product Thickness Service void Low E service void

(mm)

Crown Rafter Roll 32 200 (2x100) 0.16 0.15

Note: Rafters assumed to be 58mm wide, 241mm deep with 9.5mm web, spaced at 600 centres, with no bracing betweenthe rafters. The U-values have been calculated in accordance with BS EN ISO 6946: 1997

Typical section

PerformanceThermal performanceCrown Rafter Roll 32 has a thermal conductivityof 0.032 W/mK.


Acoustic performanceCrown Rafter Roll 32 meets the specification fora mineral wool insulation required for thecontrol of flanking sound as described inAppendix A of Robust Details.

Fire performanceCrown Rafter Roll 32 is classified as Euroclass A1 to BS EN ISO 13501-1.

Vapour resistanceKnauf Breatheline has a vapour resistance of 0.22 MNs/g.

Pitched roofs – rafter levelBetween and below rafters



Knauf Breatheline

Advantages System achieves low U-value even


Crown Rafter Roll 32 or Crown Room-in-Roof Roll 32/37 are compressible so it is easy to friction fit the product tight to the sides of rafters ensuring that there is no cold air penetration at junction between the insulation and rafters

Using Crown Rafter Roll 32 or Crown Room-in-Roof Roll 32/37 will significantly improve the acoustic performance of the roof restricting airborne noise

Crown Rafter Roll 32 or Crown Room-in-Roof Roll 32/37 can beused along with an extra layer ofplasterboard to satisfy the requirementsof Robust Details to restrict flankingsound around separating walls

ProductsCrown Room-in-Roof Roll 32/37 is made from glass mineral wool and formed into rolls whichare dimensioned to fit tightly between rafters at600mm centres. The rolls are lightweight,flexible, resilient, non-combustible, and arefaced with a low emissivity vapour control layer.The facing is wider than the roll to overlap therafters to aid fixing, and create a vapourcontrol layer. Their manufacture has a very lowimpact on the environment and is classified asZero ODP and Zero GWP*

Crown Rafter Roll 32 is made from glassmineral wool and formed into rolls which arelightweight, flexible, resilient and non-combustible - its manufacture has a very lowimpact on the environment and is classified asZero ODP and Zero GWP*



Typical constructionA pitched roof of timber rafters with tiles orslates on battens. Either with counter battens if Knauf Breatheline is pulled taught andinsulation is to the full depth of the rafters,

or alternatively without counter battens if it isdraped and the insulation stops at least 10mmbelow the top of the rafters. Insulated withCrown Rafter Roll 32 or Crown Room-in-RoofRoll 32/37 between the rafters and linedinternally with rigid foam insulation board.

InstallationKnauf Breatheline is pulled taught and laiddirectly over the rafters. 50x32mm counterbattens are nailed into the rafters with minimumpenetration of 38mm into the rafter -alternatively, helical fixings can be used with aminimum penetration of 35mm into the rafter.Tiling battens are nailed into the counterbattens. Finally, the roofing tiles or slates arefixed, to the manufacturer’s recommendations.

Friction fit Crown Rafter Roll 32 or Crown Room-in-Roof Roll 32/37 between the rafters.The insulation should be butt jointed andcontinuous with the wall insulation to avoidthermal bridging.

Finally, the PIR/PUR plasterboard laminate isnailed or screwed to the underside of the raftersat maximum 300mm centres at least 12mm infrom the board edge.

The fixings should be long enough to penetrateat least 25mm into the timber. The boards arefinished using standard drylining techniques.

With service voidWhere a service void is provided, nail a foilfaced PIR/PUR board to the rafters and tape allthe board joints and joints where the boardabuts walls, roof windows and other intrusionswith self-adhesive aluminised tape to completethe vapour control layer. The vapour controllayer formed by the PIR/PUR insulation boardand the tape should form a complete, unbroken,barrier to the warm side of the insulation. Thevapour control layer should be linked to the airbarrier in the external walls

Nail 50mm wide timber battens through thePIR/PUR board into the rafters. The battens tobe a minimum of 25mm deep but to suit therequired depth of the service void. Afterinstalling first fix services, nail plasterboard tothe timber battens. The boards are finishedusing standard drylining techniques.


Crown Room-in-Roof Roll 32 has a thermalconductivity of 0.032 W/mK.


Pr05

Knauf Breatheline

Crown Rafter Roll 32 or Crown Room-in-Roof Roll 32/37

PIR/PUR insulation board

519



Knauf Breatheline

Foil faced PIR/PUR insulation board

Crown Rafter Roll 32 or

Crown Room-in-Roof Roll 32/37

25mm service duct formed withtimber battens nailed to rafters

12.5mm plasterboard

The PIR/PUR is assumed to have a thermalconductivity of 0.023 W/mK.

Table 11 gives U-values for typical constructionswith insulation between and below the rafters.

Acoustic performanceCrown Rafter Roll 32 and Crown Room-in-RoofRoll 32/37 meet the specification for a mineralwool insulation required for the control offlanking sound as described in Appendix A of Robust Details.

Fire performanceCrown Rafter Roll 32 and Crown Room-in-RoofRoll 32/37 are classified as Euroclass A1 to BS EN ISO 13501-1.

Vapour resistanceKnauf Breatheline has a vapour resistance of0.22 MNs/g.


The U-values achieved are as shown in Table 11.

Typical specificationThe whole area of the pitched roof to beinsulated with Crown Rafter Roll 32/CrownRoom-in-Roof Roll 32/37*, friction fittedbetween the rafters. The width of theinsulation should be appropriate to thespacing of the rafters. (*Delete as appropriate)

PIR/PUR plasterboard laminate of thickness......mm with integral 12.5mm plasterboardnailed or screwed to the rafters at maximum300mm centres and finished using standarddrylining techniques.


Table 11: Typical U-values with insulation between and below rafters

U-values (W/m2K)Thickness PIR/PUR Insulation Board 25mm services void with PIR/PUR Insulation

thickness (mm) Board, thickness (mm)

(mm) 20 30 40 20 30 40


100 0.26 0.23 0.21 0.24 0.22 0.20


200 0.17 0.16 0.15 0.16 0.15 0.14

160 0.20 0.19 0.17 0.19 0.17 0.16

100 0.28 0.25 0.23 0.26 0.23 0.21


200 (2x100) 0.15 0.14 0.13 0.15 0.14 0.13

170 (2x85) 0.17 0.16 0.15 0.16 0.15 0.14

150 (2x75) 0.19 0.18 0.16 0.18 0.17 0.16

130 (2x65) 0.21 0.20 0.19 0.20 0.18 0.17

100 0.26 0.23 0.21 0.24 0.21 0.20

85 0.29 0.26 0.23 0.26 0.23 0.21

Notes: Rafters assumed to be 38mm wide at 600mm centres (6.3% bridging). The U-values have been calculated inaccordance with BS EN ISO 6946:1997 and BR443. The service void is assumed to have an R value of 0.34 m2K/W as is specified in BR443. The U-values are valid for service voids at least 25mm deep

Typical section

Pitched roofs – rafter levelBetween and below rafters with insulated plasterboard



Advantages System achieves low U-value even


Can be used with taught or draped LR underlay

Polyfoam Linerboard provides thermal and lining functions in one application

Robust nature of Polyfoam in Polyfoam Linerboard supports the plasterboard, improving its impact resistance

Using Crown Room-in-Roof Roll 32/37 willsignificantly improve the acousticperformance of the roof restrictingairborne noise

Crown Room-in-Roof Roll 32/37 can beused along with an extra layer ofplasterboard to satisfy the requirementsof Robust Details to restrict flankingsound around separating walls


Crown Room-in-Roof Roll 32/37 or PolyfoamRaftersqueeze are friction fitted (in layers ifnecessary) between the rafters. They should bebutt jointed and continuous with the wallinsulation to avoid thermal bridging.

Finally, Polyfoam Linerboard is nailed or screwed to the underside of the rafters atmaximum 300mm centres at least 12mm infrom the board edge. The fixings should be longenough to penetrate at least 25mm into thetimber. The boards are finished using standarddrylining techniques.



Polyfoam Raftersqueeze and the insulation inPolyfoam Linerboard has a thermal conductivityof 0.030 W/mK.

Table 12 gives U-values for typical constructionswith insulation between and below the rafters.

Typical constructionA pitched roof of timber rafters with tiles orslates on battens. Either with counter battens if Knauf Breatheline is pulled taught andinsulation is to the full depth of the rafters orwithout counter battens if it is draped and theinsulation stops at least a 10mm below the topof the rafters. Insulated with Crown Room-in-Roof Roll 32/37 or Polyfoam Raftersqueezebetween the rafters and lined internally withPolyfoam Linerboard.

InstallationKnauf Breatheline is pulled taught and laiddirectly over the rafters. 50x32mm counterbattens are nailed into the rafters with minimumpenetration of 38mm into the rafter.Alternatively, helical fixings can be used with aminimum penetration of 35mm into the rafter.Tiling battens are nailed into the counterbattens. Finally, the roofing tiles or slates arefixed, to the manufacturer’s recommendations.The insulation is fitted from below once the roofis weathertight.

ProductsCrown Room-in-Roof Roll 32/37 is made from glass mineral wool and formed into rolls whichare dimensioned to fit tightly between rafters at600mm centres. The rolls are lightweight,flexible, resilient, non-combustible, and arefaced with a low emissivity vapour control layer.The facing is wider than the roll to overlap therafters to aid fixing, and create a vapourcontrol layer. Its manufacture has a very lowimpact on the environment and is classified asZero ODP and Zero GWP*

Polyfoam Raftersqueeze is 100% ozonefriendly, extruded polystyrene insulation.It consists of a flexible infill piece of insulationthat fits between rafters, and allows for sometimber variation.

Polyfoam Linerboard is a laminate of Polyfoamextruded polystyrene and 9.5mm tapered edgeplasterboard.




Knauf Breatheline

Crown Room-in-Roof Roll 32/37 orPolyfoam Raftersqueeze

Polyfoam Linerboard

521



Knauf Breatheline

Roof insulation to link with wall insulation

Polyfoam Linerboard

Crown Room-in-Roof Roll 32/37 orPolyfoam Raftersqueeze

Sealant to reduce air leakage

Air barrier

Typical specificationThe whole area of the pitched roof to beinsulated with Crown Room-in-Roof Roll32/37*/ Polyfoam Raftersqueeze ......mmthick, friction fitted between the rafters. Thewidth of the insulation should be appropriateto the spacing of the rafters.(*Delete as appropriate)

Polyfoam Linerboard of thickness ......mmwith integral 9.5mm plasterboard nailed orscrewed to the rafters at maximum 300mmcentres and finished using standard dryliningtechniques.

Alternatively, refer to NBS clauses: P10/140 and 320, and K10/245

Acoustic performanceCrown Room-in-Roof Roll 32/37 meets thespecification for a mineral wool insulationrequired for the control of flanking sound asdescribed in Appendix A of Robust Details.

Compression resistanceThe rigidity of the Polyfoam in PolyfoamLinerboard offers an excellent support to thefinished internal lining and assists in theresistance of impact, helping to prolong itsservice life.

Fire performanceCrown Room-in-Roof Roll 32/37 are classified as Euroclass A1 to BS EN ISO 13501-1.

Polyfoam insulation contains a flame retardantspecifically designed to inhibit localisedignition. The boards will melt if brought intocontact with high temperature sources.However, the use of the boards will not affectthe fire rating obtained by tiled roofs whenevaluated by assessment or tested to BS 476: Part 3: 2004.

Polyfoam Linerboard is faced with 9.5mmplasterboard which offers excellent fireperformance.

Table 12: Typical U-values of roofs with insulation between and below rafters

U-values (W/m2K)Product Thickness Polyfoam Linerboard Thickness (mm)

(mm) 25.5/9.5 36/9.5 45.5/9.5

Crown Room-in-Roof Roll 32 100 0.26 0.24 0.22


160 0.20 0.19 0.18

100 0.29 0.26 0.24

Polyfoam Raftersqueeze 150 (2x75) 0.19 0.17 0.17

140 (65+75) 0.20 0.18 0.17

125 (50+75) 0.21 0.20 0.19

100 (2x50) 0.25 0.23 0.22

Notes: Rafter sizes assumed to be 38mm wide at 600mm centres (6.3% bridging) and the same depth as the insulation. The U-values have been calculated in accordance with BS EN ISO 6946:1997.

Typical section

Vapour resistanceKnauf Breatheline has a vapour resistance of 0.22 MNs/g.

Pitched roofs – rafter levelBetween and below rafters with counter battens



Advantages Can be used with taught or draped

LR underlay

Using Crown Rafter Roll 32/CrownRoom-in-Roof Roll 32/37 willsignificantly improve the acousticperformance of the roof restrictingairborne noise

Crown Rafter Roll 32/Crown Room-in-Roof Roll 32/37 can be usedalong with an extra layer ofplasterboard to satisfy therequirements of Robust Details torestrict flanking sound aroundseparating walls


rafters and to any dwarf walls. Lap all joints inthe vapour control layer. Using a self adhesivealuminised tape seal all joints and staplepunctures in the air barrier; junctions betweenthe air barrier and any walls abutting the roofand any penetrations through the roof, such asroof windows. The vapour control layer shouldbe linked to the air barrier in the external walls.Nail plasterboard to the rafters and finish usingstandard drylining techniques.





Acoustic performanceCrown Rafter Roll 32 and Crown Room-in-RoofRoll 32/37 meet the specification for mineralwool insulation required for the control offlanking sound as described in Appendix A ofRobust Details.

10mm below the top of the rafters. Insulatedwith Crown Rafter Roll 32 and Crown Room-in-Roof Roll 32/37 between the rafters. A layer ofCrown Rafter Roll 32 is installed above theCrown Room in Roll 32/37 if required and12.5mm plasterboard forms the internal lining.This is an ideal solution where the depth ofshallow rafters can be increased toaccommodate an increased thickness ofinsulation.

InstallationKnauf Breatheline is pulled taught and laiddirectly over the rafters. 50x32mm counterbattens are nailed into the rafters with minimumpenetration of 38mm into the rafter.Alternatively, helical fixings can be used with aminimum penetration of 35mm into the rafter.Tiling battens are nailed into the counterbattens. Finally, the roofing tiles or slates arefixed, to the manufacturer’s recommendations.

Friction fit, if required, a layer of Crown RafterRoll 32 into the rafter space leaving sufficientdepth to accommodate the Crown Room-in-RoofRoll 32/37 when this is installed between therafters. The insulation should be butt jointed andcontinuous with the wall insulation to avoidthermal bridging. Staple the laps of the integralvapour control layer to the underside of the

ProductsCrown Room-in-Roof Roll 32/37 is made fromglass mineral wool and formed into rolls whichare dimensioned to fit tightly between rafters at600mm centres. The rolls are lightweight,flexible, resilient, non-combustible and arefaced with a low emissivity vapour control layer.The facing is wider than the roll to overlap therafters to aid fixing, and create a vapourcontrol layer. Their manufacture has a very lowimpact on the environment and is classified asZero ODP and Zero GWP*

Crown Rafter Roll 32 is made from glassmineral wool and formed into rolls which arelightweight, flexible, resilient and non-combustible. Its manufacture has a very lowimpact on the environment and is classified asZero ODP and Zero GWP*



Typical constructionA pitched roof of timber rafters set out at600mm centres with tiles or slates on battens.Either with counter battens if Knauf Breathelineis pulled taught and insulation is to the fulldepth of the rafters or without counter battens ifit is draped and the insulation stops at least

Knauf Breatheline

Pr07


Knauf Breatheline

12.5mm plasterboard

523



Knauf Breatheline

Crown Room-in-Roof Roll32/37 with integral vapourcontrol layer

Crown Room-in-Roof Roll32/37 with integral vapourcontrol layer

Counter battens a 600mmcentres (as rafters)


12.5mm plasterboard

12.5mm plasterboard

Typical specificationThe whole area of the pitched roof to beinsulated with Crown Rafter Roll 32/CrownRoom-in-Roof Roll 32/37*, friction fittedbetween the rafters. The width of theinsulation should be appropriate to thespacing of the rafters.

Timber battens to be nailed to the undersideof the rafters. A vapour control layer to bestapled to the timber battens.(*Delete as appropriate)

12.5mm plasterboard nailed or screwed tothe timber battens at maximum 300mmcentres and finished using standard dryliningtechniques.

Alternatively, refer to NBS clauses.

Fire performanceCrown Rafter Roll 32 and Crown Room-in-RoofRoll 32/37 are classified as Euroclass A1 to BSEN ISO 13501-1.



The U-value achieved is as shown in Table 13.

Table 13: Typical U-values of roofs with insulation between rafters and battens

Product Thickness U-values (W/m2K)

Between rafters Crown Rafter Roll 32

(mm) 50 65 75 85 100

Crown Room-in-Roof Roll 32 100 0.24 0.21 0.20 0.19 0.17


(mm) 50 65 75 85 100


160 0.19 0.17 0.16 0.15 0.15

100 0.26 0.22 0.21 0.20 0.18

Rafters assumed to be 38mm wide at 600mm centres (6.3% bridging). The U-values have been calculated in accordancewith BS EN ISO 6946:1997.

Typical section

Timber battens at 600mmcentres

Advantages Can be used with taught or draped

LR underlay

Using Crown Rafter Roll 32/CrownRoom-in-Roof Roll 32/37 willsignificantly improve the acoustic performance of the roof restricting airborne noise

Crown Rafter Roll 32/Crown Room-in-Roof Roll 32/37 can be usedalong with an extra layer ofplasterboard to satisfy therequirements of Robust Details torestrict flanking sound aroundseparating walls

Using a low emissivity vapour control layer increases the thermal resistance of the service void, thus improving the U-value of the construction

Pr08

Pitched roofs – rafter levelBetween rafters with service void



ProductsCrown Room-in-Roof Roll 32/37 is made from glass mineral wool and formed into rolls whichare dimensioned to fit tightly between rafters at600mm centres. The rolls are lightweight,flexible, resilient, non-combustible, and are isfaced with a low emissivity vapour control layer.The facing is wider than the roll to overlap therafters to aid fixing, and create a vapourcontrol layer. Their manufacture has a very lowimpact on the environment and is classified asZero ODP and Zero GWP*

Crown Rafter Roll 32 is made from glassmineral wool and formed into rolls which arelightweight, flexible, resilient and non-combustible. Its manufacture has a very lowimpact on the environment and is classified asZero ODP and Zero GWP*Knauf Breatheline is a breathable membranewith a polypropylene non-woven coating onboth sides – see also page 534.* Ecohomes and Code for Sustainable Homes classification

Knauf Breatheline

Typical constructionA pitched roof of timber rafters set out at 600mm centres with tiles or slates on battens. Either with counter battens if Knauf Breathelineis pulled taught and insulation is to the full depth of the rafters or without counter battens ifit is draped and the insulation stops at least10mm below the top of the rafters. Insulatedwith Crown Rafter Roll 32 and Crown Room-in-Roof Roll 32/37 between the rafters. A layer ofCrown Rafter Roll 32 is installed above theCrown Room in Roll if required. The integrallow emissivity vapour control layer has laps thatfix to the rafter and face onto a services voidformed with timber battens nailed along the lineof the rafters. 12.5mm plasterboard forms theinternal lining.InstallationKnauf Breatheline is pulled taught and laiddirectly over the rafters. 50x32mm counterbattens are nailed into the rafters withminimum penetration of 38mm into the rafter.Alternatively, helical fixings can be used with aminimum penetration of 35mm into the rafter.Tiling battens are nailed into the counterbattens. Finally, the roofing tiles or slates arefixed, to the manufacturer’s recommendations.

Friction fit, if required, a layer of Crown RafterRoll 32 into the rafter space leaving sufficientdepth to accommodate the Crown Room-in-RoofRoll 32/37 when this is installed between the rafters. The insulation should be butt jointed and continuous with the wall insulation to avoid thermal bridging. Staple the laps of the integral vapour control layer to the underside of the rafters and to any dwarf walls. Lap all joints in the vapour control layer. Using a self adhesive aluminised tape seal all joints and staple punctures in the air barrier; junctions betweenthe air barrier and any walls abutting the roof and any penetrations through the roof, such as roof windows. The vapour control layer should be linked to the air barrier in the external walls.Nail 50mm wide timber battens along the lineof the rafters. The battens to be a minimum of 25mm deep butto suit the required depth of the service void.After installing first fix services, nailplasterboard to the timber battens. Finish theplasterboard using standard dryliningtechniques.

Knauf Breatheline

Crown Rafter Roll 32 / Crown Room-in-Roof Roll 32/37

Counter battens

Integral low emissivity vapourcontrol layer

12.5mm plasterboardTimber battens to form service void

Typical specificationThe whole area of the pitched roof to beinsulated with Crown Rafter Roll 32 andCrown Room-in-Roof Roll 32*/37*,… mmthick friction fitted between the rafters. Thewidth of the insulation should be appropriateto the spacing of the rafters.(*Delete as appropriate)The integral low-emissivity vapour control layer to be stapled to the rafters with alljoints well sealed. 50x25mm timber battens nailed along the line of the rafters to form a service void.12.5mm plasterboard nailed or screwed tothe timber battens at maximum 300mmcentres and finished using standard dryliningtechniques.


525



PerformanceThermal performanceCrown Rafter Roll 32 has a thermalconductivity of 0.032 W/mK.

Crown Room-in-Roof Roll 32 has a thermal

conductivity of 0.032 W/mK.



Acoustic performanceCrown Rafter Roll 32 and Crown Room-in-RoofRoll 32/37 meet the specification for a mineralwool insulation required for the control offlanking sound as described in Appendix A ofRobust Details.Fire performanceCrown Rafter Roll 32 and Crown Room-in-RoofRoll 32/37 are classified as Euroclass A1 to BSEN ISO 13501-1.Vapour resistanceKnauf Breatheline has a vapour resistance of0.22 MNs/g.

Knauf Breatheline

Integral low emissivityvapour control layer

Crown Rafter Roll 32 /


25mm service void

12.5mm plasterboard

Table 14: Typical U-values with insulation between rafters with service void

Product Thickness U-values (W/m2K)

Between rafters Crown Rafter Roll 32

(mm) 50 65 75 85 100



(mm) 50 65 75 85 100


160 0.18 0.16 0.15 0.15 0.14

100 0.24 0.21 0.20 0.19 0.17

Note: Rafters assumed to be 38mm wide at 600 centres (6.3 % bridging). The U-values have been calculated in accordancewith BS EN ISO 6946: 1997.

Low emissivity airspace is assumed to have a thermal resistance of 0.34m2K/W

12.5mm plasterboard

Typical section

Refurbishment of existing roofsThis is a valid solution for the refurbishment ofan existing roof where the roof tiles and roof tileunderlay are not being removed. In thesecircumstances a continuous 50mm gap must be maintained between the insulation and theroof tile underlay which is vented at the eavesand ridge.

The U-values achieved are shown in Table 14.

Advantages Using Crown Rafter Roll 32/Crown

Room-in-Roof Roll 37 willsignificantly improve the acousticperformance of the roof restrictingairborne noise

Crown Rafter Roll 32/Crown Room-in-Roof Roll 37 can be usedalong with an extra layer ofplasterboard to satisfy therequirements of Robust Details torestrict flanking sound aroundseparating walls

Long rolls with greater coverage perroll than other equivalent products

Pr09Knauf BreathelineThinsulex

Pitched roofs – rafter levelBetween rafters with Multifoil



ProductsCrown Room-in-Roof Roll 37 is made from glass mineral wool and formed into rolls whichare dimensioned to fit tightly between rafters at600mm centres. The rolls are lightweight,flexible, resilient, non-combustible, and arefaced with a low emissivity vapour control layer.The facing is wider than the roll to overlap therafters to aid fixing, and create a vapourcontrol layer. Its manufacture has a very lowimpact on the environment and is classified asZero ODP and Zero GWP*

Crown Rafter Roll 32 is made from glassmineral wool and formed into rolls which arelightweight, flexible, resilient and non-combustible. Its manufacture has a very lowimpact on the environment and is classifiedas Zero ODP and Zero GWP*

Thinsulex™ Multi-foil is an insulation productcomprising multilayers of insulation separatedby multiple layers of sheets of reflectivesurfaces.



Typical constructionKnauf Breatheline is pulled taught and laiddirectly over the rafters. 50x32mm counterbattens are nailed into the rafters with minimumpenetration of 38mm into the rafter -alternatively, helical fixings can be used with aminimum penetration of 35mm into the rafter.Tiling battens are nailed into the counterbattens. Finally, the roofing tiles or slates arefixed, to the manufacturer’s recommendations.

With Crown Rafter Roll 32 or Crown Room-in-Roof Roll 37 between the rafters. ThinsulexMulti-foil is stapled to the underside of therafters with 12.5mm foil backed plasterboardas the internal lining.

The full thermal performance of Thinsulex is only achieved when there is an airspace onboth sides of the insulation.

25mm deep cross battens are nailed throughthe Thinsulex into the rafters to create anairspace below the Thinsulex.

InstallationKnauf Breatheline is pulled taught and laiddirectly over the rafters. Counter battens arenailed into the rafters. Tiling battens are nailedinto the counter battens and the roofing tiles or slates are fixed, to the manufacturer’srecommendations.

The insulation is fitted from below once the roofis weathertight. Friction fit Crown Room-in-RoofRoll 37 between the rafters. Alternatively frictionfit Crown Rafter Roll 32 between the rafters (inlayers if necessary). The insulation should bebutt jointed and continuous with the wallinsulation to avoid thermal bridging.

Staple Thinsulex Multi-foil to the underside of therafters. Tape all joints with aluminised tape.

Nail 32x25mm timber cross battens at 600mmcentres into the rafters. After installing first fixservices, nail foil backed plasterboard to thetimber battens. Finish the plasterboard usingstandard drylining techniques.



Thermal resistance of Thinsulex Multi-foilincluding air layers and bridging is 1.37 m2K/W (1 airspace)1 and 1.69 m2K/W (2 airspaces)2.

Table 15 gives U-values for typical constructionswith insulation between the rafters andThinsulex Multifoil, with either one or twoairspaces, below the rafters.

Knauf Breatheline



Counter battens

Thinsulex™ Multi-foil

12.5mm foil backed plasterboard Service void

Typical specificationThe whole area of the pitched roof to beinsulated with Crown Rafter Roll 32 or Crown Room-in-Roof Roll 37, friction fittedbetween the rafters.(*Delete as appropriate)

The width of the insulation should beappropriate to the spacing of the rafters.

Thinsulex Multi-foil to be stapled to theunderside of the rafters, with all joints taped with aluminised tape.

32x25mm timber cross battens to be nailedinto the rafters at 600mm centres. 12.5mmfoil backed plasterboard to be nailed orscrewed to the timber battens at maximum300mm centres and finished using standarddrylining techniques.


527



Knauf Breatheline

Thinsulex Multi-foil insulation

Crown Rafter Roll 32 orCrown Room-in-Roof Roll37 between rafters

32x25mm cross battens at 600mm centres

12.5mm foil backed plasterboard

Counter battens

Acoustic performanceCrown Rafter Roll 32 and Crown Room-in-RoofRoll 32/37 meet the specification for a mineralwool insulation required for the control offlanking sound as described in Appendix A of Robust Details.

Fire performanceCrown Rafter Roll 32 and Crown Room-in-RoofRoll 32/37 are classified as Euroclass A1 to BS EN ISO 13501-1.

Thinsulex Multi-foil will not contribute to thedevelopment stages of a fire or present a smoke or toxic hazard.



The U-value achieved is as shown in Table 15.

Table 15: Typical U-values for roofs with insulation between and below rafters, with a service void

Product Thickness Thinsulex (2 air spaces)2 Thinsulex (1 air spaces)1

(mm) U-values (W/m2K) U-values (W/m2K)


170 (2x85) 0.16 0.16

150 (2x75) 0.17 0.18

130 (2x65) 0.19 0.20

100 0.22 0.23

Crown Room-in-Roof Roll 37 200 0.15 0.16

160 0.18 0.19

100 0.23 0.25

Note: Rafters assumed to be 48mm wide at 600 centres (8% bridging). The U-values have been calculated in accordancewith BS EN ISO 6946: 1997

Typical section

Knauf Breatheline

Polyfoam Pitched Roofboard

Counter battens

Polyfoam RaftersqueezePlasterboard


Pitched roofs – rafter levelBetween and above rafters



Advantages Polyfoam Pitched Roofboard can

be used with any rafter spacing

Vertical joints do not need to occur at rafters, making installation quick and simple

Polyfoam is lightweight yet very strong, making it easy to handle on the roof

Polyfoam Raftersqueeze fits tightlyto the sides of rafters

Once Polyfoam Pitched Roofboard is fixed inplace, Polyfoam Raftersqueeze is friction fittedbetween the rafters. If rafter centres are otherthan 600mm (e.g. 450mm, 300mm etc) cut theboard slightly oversize to fit and use theremaining squeeze on one edge to push fitbetween rafters. They boards should be pushedup to the underside of the Polyfoam PitchedRoofboard, so there are no gaps. A timberbatten or noggin fixed into the rafter below thePolyfoam Raftersqueeze (optional) can be usedto hold the board in position.

There is an alternative fixing method for counterand tiling battens which is described in BritishBoard of Agrément Certificate 06/4386.

InstallationA timber stop rail is fixed to the ends of therafters. Polyfoam Pitched Roofboard is fittedstarting from the timber stop rail, with all boardstightly butted.

The board is not suitable to be walked on, asdefined in HSE33, except when covered withsupporting timbers.

Knauf Breatheline, is pulled taught and laiddirectly over the insulation.

50 x 32mm counter battens are nailed throughthe Knauf Breatheline and Polyfoam PitchedRoofboard and into the rafters using spiralfixings such as Helifix Inskew 600 or BuildexRG, with minimum penetration into the rafter of35mm. Tiling battens are laid across the roofand nailed into the counter battens. Tiles shouldbe stacked so that they bear directly over therafters. Finally, the roofing tiles or slates arefixed to the manufacturer’s recommendations.

ProductsPolyfoam Pitched Roofboard is a 100% ozonefriendly, extruded polystyrene, rigid boardinsulation system. It is lightweight with shiplapedge details that do not have to meet directlyon top of rafters, making installation very quickand simple.

Polyfoam Raftersqueeze is a 100% ozonefriendly, extruded polystyrene, rigid boardinsulation – it is lightweight and consists of aflexible infill piece of insulation that fits betweenrafters, and allows for some timber variation.


Typical constructionA pitched roof of timber rafters with tiles orslates on battens and Knauf Breatheline.Insulated with Polyfoam Pitched Roofboard laidover rafters and Polyfoam Raftersqueeze fittedbetween rafters.

Knauf BreathelinePolyfoam Pitched Roofboard

Pr10

529



Typical specificationInsulation laid over rafters to be PolyfoamPitched Roofboard, ......mm thick. KnaufBreatheline is then pulled taught and laiddirectly over the insulation and held in placeby 50 x 32mm counter battens nailedthrough the boards, into the rafters. The tilingbattens to be nailed into the counter battens.

Insulation between the rafters to be PolyfoamRaftersqueeze, supported on battens nailedto the side of the rafters (optional).

Alternatively, refer to NBS clauses: K11/670 and P10/140 and 320

PerformanceThermal performancePolyfoam Pitched Roofboard has a thermalconductivity of 0.029 W/mK.

Polyfoam Raftersqueeze has a thermalconductivity of 0.030 W/mK.

Table 16 gives U-values for typicalconstructions.

Table 16: Typical U-values of pitched warm roofs insulated above and between raftersU-values (W/m2K) of Polyfoam Pitched

Insulation between rafters Thickness Roofboard thickness over rafters (mm)

(mm) 35 50 60 75

Polyfoam Raftersqueeze 150 (75+75) 0.17 0.16 0.15 0.14

125 (75+50) 0.20 0.18 0.17 0.15

100 (50+50) 0.23 0.21 0.19 0.17

75 0.28 0.24 0.22 0.20Notes: Rafter sizes assumed to be 38mm wide at 600mm centres (6.3% bridging). The U-values have been calculated in accordance with BS EN ISO 6946:1997.

Compression resistanceThe rigidity of Polyfoam Pitched Roofboardmakes the board easy to handle and less proneto site damage than less robust materials.

Moisture resistancePolyfoam Pitched Roofboard is highly resistantto moisture absorption and will perform asstated if exposed to moisture in use.

Fire performanceThe boards contain a flame retardantspecifically designed to inhibit localisedignition. The boards will melt if brought intocontact with high temperature sources.However, the use of the boards will not affectthe fire rating obtained by tiled roofs whenevaluated by assessment or tested to BS 476:Part 3: 2004. The underside of the raftersshould be faced with 12.5mm plasterboard to provide fire protection.

Counter battens

Knauf Breatheline


Polyfoam Raftersqueeze


Polyfoam Pitched Roofboard over rafters


Air barrier

Typical section

Timber Stop Rail

Pitched roofs – rafter levelBetween and above rafters



Advantages Non-combustible insulation gives

fire safe solution

No ventilation required at eaves orroof voids

A breathable and vapour permeablesystem

Significantly improves the acousticperformance of the roof

Crown Rafter Roll 32 and Crown Room-in-Roof Roll 37 can be used along with an extra layer of plasterboard to satisfy the requirements of Robust Details to restrict flanking sound around separating walls


Counter battens should be fixed through theRocksilk Pitched Roof Slab boards using spiralfixings such as Helifix Inskew 600 or BuildexRG, with a minimum penetration into the rafterof 35mm.

The fixings are to be installed at no greater than 400mm centres along the battens.

From below, Crown Room-in-Roof Roll 37 orCrown Rafter Roll 32 is simply friction fittedbetween the rafters. The insulation should befriction fitted between the rafters so that it is indirect contact with the Rocksilk Pitched RoofSlab, with no air gaps between the two layersof insulation.

To avoid a thermal bridge at the eaves, RocksilkPitched Roof slabs should be cut to shape to linkthe roof and wall insulation.

A continuous vapour control layer should befixed to the underside of the rafters.



Typical constructionA pitched roof of timber rafters with tiles orslates on battens and counter battens and KnaufBreatheline. Insulated with Rocksilk Pitched RoofSlab laid over the rafters and Crown Room-in-Roof Roll 37 or Crown Rafter Roll 32, frictionfitted between the rafters.

InstallationA timber stop rail is fixed to the ends of therafters. Rocksilk Pitched Roof Slab is fittedstarting from the timber stop rail, with all slabstightly butted.

Rocksilk Pitched Roof Slab should be laid acrossthe finished rafters with staggered joints. Theslabs should be cut to length to match thespacings of the rafters.

Knauf Breatheline can be installed either belowthe counter battens (as shown above), or abovethe counter battens. When installed above thecounter battens Knauf Breatheline should bedraped by no less than 10mm.

ProductsCrown Room-in-Roof Roll 37 is made from glass mineral wool and formed into rolls whichare dimensioned to fit tightly between rafters at600mm centres. The rolls are lightweight,flexible, resilient, non-combustible, and arefaced with a low emissivity vapour control layer.The facing is wider than the roll to overlap therafters to aid fixing, and create a vapourcontrol layer. Its manufacture has a very lowimpact on the environment and is classified asZero ODP and Zero GWP*


Rocksilk Pitched Roof Slab is a compressionresistant, water repellent, rock mineral woolslab specifically developed for over rafter(sarking) insulation. Its manufacture has a verylow impact on the environment and is classifiedas Zero ODP and Zero GWP*


Knauf Breatheline

Rocksilk Pitched Roof Slab

Counter battens

Crown Rafter Roll 32 or Crown Room-in-Roof Roll 37 12.5mm plasterboard


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Typical specificationInsulation laid over rafters to be RocksilkPitched Roof Slab, ......mm thick, locatedover the rafters. All boards tightly butted andwith staggered joints. Knauf Breathelineshould then be laid over the insulation withthe edges lapped.

The insulation and underlay to be held inplace by 50 x 32mm counter battens fixedthrough the boards, into the rafters. The tilingbattens to be nailed into the counter battens.

Crown Room-in-Roof Roll 37 or Crown RafterRoll 32......mm thick, to be friction fittedbetween the rafters. The width of the insulation should beappropriate to the spacing of the rafters.

Alternatively, refer to NBS clauses: K11/670 and P10/140 and 320

PerformanceThermal performanceRocksilk Pitched Roof Slab has a thermalconductivity of 0.038 W/mK.

Crown Rafter Roll 32 has a thermal conductivityof 0.032 W/mK.


Table 17 gives U-values for typicalconstructions.

Acoustic performanceCrown Rafter Roll 32 and Crown Room-in-RoofRoll 37 meet the specification for mineral woolinsulation required for the control of flankingsound as described in Appendix A of RobustDetails.

Fire performanceCrown Rafter Roll 32, Crown Room-in-Roof Roll37 and Rocksilk Pitched Roof Slab are classifiedas Euroclass A1 to BS EN ISO 13501-1.

Table 17: Typical U-values of pitched roofs with insulation between and over rafters

U-values (W/m2K)Insulation Thickness Rocksilk Pitched Roof Slab (mm)

(mm) 50 70

Crown Room-in-Roof Roll 37 200 0.16 0.14

160 0.18 0.17

100 0.25 0.22


170 (2x85) 0.16 0.15

150 (2x75) 0.18 0.16

130 (2x65) 0.20 0.18

100 0.23 0.21Notes: Rafter sizes assumed to be 38mm wide at 600mm centres (6.3% bridging) and the same depth as the insulation. The U-values have been calculated in accordance with BS EN ISO 6946:1997.

Counter battens

Knauf Breatheline


Crown Room-in-Roof Roll 37or Crown Rafter Roll 32


Rocksilk Pitched Roof Slab


Air barrier

Typical section

Pitched roofs – rafter levelBetween and below rafters – existing roof



Advantages Robust nature of Polyfoam in

Linerboard supports the plasterboard, improving its impact resistance

Crown Rafter Roll 32/Crown Room-in-Roof Roll 32/37 andPolyfoam Raftersqueeze friction fit tightly to rafters

Using Crown Rafter Roll 32/Crown Room-in-Roof Roll 32/37 will significantly improve the acousticperformance of the roof restrictingairborne noise

Suitable for upgrading existing roof


Alternatively, Polyfoam Raftersqueeze is fittedbetween the rafters. If rafter centres are otherthan 600mm (e.g. 450mm, 300mm etc) cut theboard slightly oversize to fit and use theremaining squeeze on one edge to push fitbetween rafters.

Finally, Polyfoam Linerboard is nailed orscrewed to the underside of the rafters atmaximum 300mm centres at least 12mm infrom the board edge. The fixings should be longenough to penetrate at least 25mm into thetimber. The boards are finished using standarddrylining techniques.

Typical constructionA pitched roof of timber rafters with tiles orslates on battens on an HR type underlay.Insulated with Crown Room-in-Roof Roll 32/37,Crown Rafter Roll 32 or PolyfoamRaftersqueeze between the rafters and linedinternally with Polyfoam Linerboard.

There must be a continuous 50mm gap abovethe insulation which is vented at the eaves andridge. This is the most popular method forinsulating an existing roof when a loft isconverted to habitable accommodation.

InstallationCrown Room-in-Roof Roll 32/37 or CrownRafter Roll 32 is friction fitted (in layers ifnecessary) between the rafters, taking care toleave a 50mm gap above the insulation. The rolls should be butt jointed and continuouswith the wall insulation to avoid thermalbridging.

Polyfoam Linerboard

ProductsCrown Room-in-Roof Roll 32/37 is made from glass mineral wool and formed into rolls whichare dimensioned to fit tightly between rafters at600mm centres. The rolls are lightweight,flexible, resilient, non-combustible, and arefaced with a low emissivity vapour control layer.The facing is wider than the roll to overlap therafters to aid fixing, and create a vapourcontrol layer. Their manufacture has a very lowimpact on the environment and is classified asZero ODP and Zero GWP*


Polyfoam Raftersqueeze is a 100% ozonefriendly, extruded polystyrene insulation. Itconsists of a flexible infill piece of insulation thatfits between rafters, and allows for some timbervariation

Polyfoam Linerboard is a laminate of Polyfoamextruded polystyrene and 9.5mm tapered edgeplasterboard


Optional timber spacer battens to maintain ventilation space above insulationInsulation between rafters

Polyfoam Linerboard

Pr12

50mm clear ventilation space between membrane and insulation

Crown Rafter Roll 32 or Crown Room-in-Roof Roll 32/37or Polyfoam Raftersqueeze

HR type underlay drapedbetween rafters

533



50mm ventilation path


Polyfoam Linerboard


Air barrier

Typical specificationThe whole area of the pitched roof to beinsulated with Crown Room-in-Roof Roll32/37*/Crown Rafter Roll 32/PolyfoamRaftersqueeze* ......mm thick, friction fittedbetween the rafters, with a continuous 50mmventilation space above the insulation. Thewidth of the insulation should be appropriateto the spacing of the rafters.

Polyfoam Linerboard of thickness .....mm withintegral 9.5mm plasterboard nailed orscrewed to the rafters at maximum 300mmcentres and finished using standard dryliningtechniques.(*Delete as appropriate)

Alternatively, refer toNBS clauses: P10/140and 320, and K10/245



Crown Rafter Roll 32 has a thermal conductivityof 0.032 W/mK.

Polyfoam Raftersqueeze and the insulation inPolyfoam Linerboard has a thermal conductivityof 0.030 W/mK.

Table 18 (opposite) gives U-values for typicalconstructions with insulation between and belowthe rafters.

Compression resistanceThe rigidity of the Polyfoam in PolyfoamLinerboard offers an excellent support tothe finished internal lining and assists inthe resistance of impact, helping to prolongits service life.

Fire performanceCrown Room-in-Roof Roll 32/37 and CrownRafter Roll 32 are classified as Euroclass A1 toBS EN ISO 13501-1.

Table 18: Typical U-values of roofs with insulation between and below rafters

U-values (W/m2K)Product Thickness Polyfoam Linerboard Thickness (mm)

(mm) 25.5/9.5 36/9.5 45.5/9.5


Crown Rafter Roll 32 200 (2x100) 0.15 0.15 0.14

160 (75+85) 0.19 0.17 0.17

100 0.26 0.24 0.22


160 0.20 0.19 0.18

100 0.28 0.26 0.24

Polyfoam Raftersqueeze 150 (2x75) 0.20 0.18 0.17

140 (65+75) 0.21 0.19 0.18

125 (50+75) 0.22 0.21 0.20

100 (2x50) 0.26 0.24 0.22Notes: Rafter sizes assumed to be 38mm wide at 600mm centres (6.3% bridging) and the same depth as the insulation.The U-values have been calculated in accordance with BS EN ISO 6946:1997.

Typical sectionCrown Room-in-Roof Roll 32/37 or

Crown Rafter Roll 32or Polyfoam Raftersqueeze

Polyfoam insulation contains a flame retardantspecifically designed to inhibit localisedignition. The boards will melt if brought intocontact with high temperature sources andare classed as combustible.

However, the use of the boards will not affectthe fire rating obtained by tiled roofs whenevaluated by assessment or tested to BS 476:Part 3: 2004.

Polyfoam Linerboard is faced with 9.5mmplasterboard which offers excellent fireperformance.

Pitched roofsVapour permeable underlays



ProductsKnauf Breatheline is a breathable membranewith a polypropylene non-woven coating onboth sides. It is classified as a type LR roof tile underlay according to the specification inBS 5250.

Typical constructionKnauf Breatheline can be used in both warmand cold pitched roofs.

In cold pitched roofs, Knauf Breatheline isnormally draped about 10-15mm between therafters to allow wind driven rain and snow todrain below the tiling battens into the gutter. At the eaves, Knauf Breatheline should not beexposed to the long term effects of sunlight –a type 5U felt underlay or eaves carrier shouldbe used and dressed into the gutter.

In warm pitched roofs, where the insulationstops short of the top of the rafters, it can bedraped 10-15mm between the rafters.

In warm pitched roofs where the membrane isfully supported by insulation or sarking boards,counter battens are required.

Knauf Breatheline

Advantages Low vapour resistance – Knauf

Breatheline is classified as an LR underlay as defined in BS5250

Allows the continuous diffusion of moisture from the whole area of the pitched roof under all wind conditions

Waterproof to wind driven rain and snow

Excellent nail tear and tensile strength

Can be laid directly over insulation or sarking boards as there is no capillary action through the underlay

When installed in accordance with the BBA Certificate there is no requirement for ventilation of the roof space

InstallationAlways use non-ferrous staples or nails to fixKnauf Breatheline at 300mm centres.

Use the dotted lines printed on the underlay to indicate the size of laps when layingsubsequent lengths of underlay.

Unsupported underlaysKnauf Breatheline is laid parallel to the eavesand draped between the rafters as traditionaltiling underlays.

Knauf Breatheline underlays can also be draped over counter battens in boarded andwarm roofs.

Supported underlaysWhenever rigid insulation or timber boarding is fixed directly onto the rafters, counter battensmust be used.

Counter battens can either be fixed directly onto the boarding with Knauf Breathelinedraping between the counter battens or it canbe laid directly over the boarding or insulationand the counter battens fixed on top.

PerformanceVapour resistanceKnauf Breatheline has a vapour resistance of 0.22 MNs/g.

Knauf Breatheline

Pr13

Table 19: Ventilation requirements for LR underlays

LR underlay approval type of Size of ventilation openings at:ceiling eaves high level

No technical approval Normal 7mm 5mm

No technical approval Well sealed* 3mm 5mm

With technical approval Normal 7mm 5mm

With technical approval Well sealed* Not required Not required

*See page 152 for definition of well sealed ceiling.

535



Alternative positions for Knauf Breatheline

Cold roof

Warm roof – insulation stops short of top of rafters

Warm roof – fully supported

Warm roof – draped over counter battens

Typical specification

Fully supported underlayKnauf Breatheline should be laid horizontallyacross the roof slope, pulled taught, with thebottom edge lapping the eaves tray by150mm. Fix with non-ferrous nails or staplesto each rafter at maximum 300mm centres.Nail counter battens along the line of therafters. Nail the tiling battens to the counterbattens at centre required by the roof finish.Use the battens as footholds to position andfix the next roll. Specification should bebased on, and referenced to BBA Certificate03/4014. Horizontal and vertical laps to bein accordance with BS 5534: 2003.

Unsupported underlayKnauf Breatheline should be laid horizontallyacross the roof slope, with the bottom edgelapping the eaves carrier by 150mm. Drapethe underlay 10-15mm between rafters. Fixwith non-ferrous nails or staples to each rafterat maximum 300mm centres. Nail the tilingbattens to the rafters*/counter battens* atcentre required by the roof finish. Use thebattens as footholds to position and fix thenext roll. Specification should be based on,and referenced to BBA Certificate 03/4014.Horizontal and vertical laps to be inaccordance with BS 5534: 2003.

Knauf Breatheline draped between rafters

Knauf Breatheline draped between rafters

Insulation between raftersstops 10-15mm short of top ofrafters

Knauf Breatheline fully supported

Counter batten

Insulation fully fills space between rafters

Tiling batten

Knauf Breatheline draped overcounter battens



Counter batten

Pitched roofsTypical eaves details



Eaves detail with boxed eaves

Knauf Breatheline pulled taught over Polyfoam Pitched Roofboard laid over rafters

Polyfoam Raftersqueeze between rafters

Vapour control layer behind plasterboard

Crown DriTherm to provide continuity insulation and minimise air leakage into the roof space

Wall plate bedded on a continuous mortar bed

Ceiling/drylining junction sealed with plaster, adhesive or sealant to reduce air leakage

Double nogging with vapour control layer between sealed to provide continuous air barrier

Scottish eaves detail with exposed rafter feet

Knauf Breatheline fully supported on sarking boards

Roof and wall insulation butted togetherto ensure continuity of insulation

Crown Room-in-Roof Roll 32/37 between rafters

Wall plate bedded on a continuous mortar bed

Ceiling/drylining junction sealed with plaster,adhesive or sealant to reduce air leakage

Flat ceiling installed first and junctionsealed with plaster, adhesive or sealantto reduce air leakage

Polyfoam Linerboard

537



Pitched roofsTypical verge details

Polyfoam Pitched Roofboard over rafters


Polyfoam Raftersqueeze between rafters

Crown DriTherm Cavity Slab taken up to top of wall

Typical overhanging verge detail with insulation over and between rafters

Fully fill the void between the wall head and the over rafter insulation

Install compressible insulation between last rafter and wall

Ceiling/drylining junction sealed with plaster, adhesive or sealant to reduce air leakage

Typical overhanging verge detail with insulation between and under rafters

Crown Room-in-Roof Roll 32/37 between rafters

Polyfoam Linerboard

Crown DriTherm Cavity Slab taken up to top of wall

Dry verge

Ceiling/drylining junction sealed with plaster,adhesive or sealant to reduce air leakage

Crown Room-in-Roof Roll 32/37 over the top of thewall, within the gable ladder

10mm drape in Knauf Breatheline

Pitched roofsTypical ceiling level details



Detail with exposed eaves

Knauf Breatheline pulledtaught over rafters to providewindproof layer

100mm Crown Loft Roll 44 has an R-value of 2.25 m2K/W

Tiling battens on counter battens

Gutter skirt dressed into gutter

Insulation pushed up tight against Knauf Breatheline andcontinuous with wall insulation

Space between rafters well sealed toprevent air infiltration into loft space

Crown Loft Roll 40 or 44in two layers

Crown Loft Roll 40 or 44 intwo layers

Boxed eaves

Knauf Breatheline pulled taught overrafters to provide windproof layer

100mm Crown Loft Roll 44 has an R-value of 2.25 m2K/W

Tiling battens on counter battens


Fully enclosed boxed eaves with noprovision for ventilation

Insulation pushed up tight against Knauf Breatheline andcontinuous with wall insulation

Scottish example with exposed rafter feetSlates nailed directly to sarkingboard

Knauf Breatheline fully supported onsarking boards

Space between rafters well sealed toprevent air infiltration into loft space

Crown Loft Roll 40 or 44in two layers

Insulation pushed up tight against sarkingboard and continuous with wall insulation

100mm Crown Loft Roll 44 hasan R-value of 2.25 m2K/W


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Crown Room-in-Roof Roll 32/37between rafters

Crown DriTherm Cavity Slabscut to shape to link wall androof insulation

PolyfoamLinerboard butted withsealant at junction

Longitudinal tie

Counter battens fixed to rafters

Knauf Breatheline pulled taught over rafters

Foil facing

Ceiling/drylining junction sealed withplaster, adhesive or sealant to reduceair leakage

Double nogging with vapourcontrol layer between andsealed to provide continuousair barrier

Vapour control layer tolink Polyfoam Linerboardand wall air barrier

Crown Room-in-Roof Roll 32/37 between studs

Seal betweenvapour control layer and PolyfoamLinerboard

PolyfoamLinerboard forms air barrier

Gutter skirt dressedinto gutter

Crown Loft Roll 40 or 44 intwo layers

www.knaufinsulation.co.uk

www.thinkinsulation.com

Knauf Insulation Ltd.PO Box 10Stafford RoadSt HelensMerseysideWA10 3NS

Customer Service (Sales)Tel: 0844 800 0135Fax: 01744 612 007email: [email protected]

Technical Advisory Centre (TAC)Tel: 01744 766666Fax: 01744 766667email: [email protected]

LiteratureTel: 08700 668 660Fax: 0870 400 5797email: [email protected]

August 2008: Issue 1

Ref: KB57408

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