TIMBER FRAME - Encon Insulation · specifically for framed constructions. the compressible edge of rockwool Flexi expands into voids ... and energy consumption in timber frame buildings

Superior 4 in 1 insulation

TIMBER FRAMESOLUTIONS GUIDE

CI/SfB l l l Ym1 l (M2) lJuly 2008

SUPERIOR 4 IN 1 INSULATION SOLUTIONS

Timber frame buildings are becoming increasingly popular amongst specifiers, designers and contractors looking for a forward thinking, cost effective and sustainable construction method. This, coupled with the rigours of modern government legislation, dictates that your insulation must perform on more than one front. Rockwool manufacture a range of 4 in 1 insulation solutions offering superior thermal, fire, acoustic and sustainable performance. Four benefits, one insulation.

tHeRmAl

Timber frame properties lose thermal energy in three ways – through the building envelope, openings and ventilation (particularly unwanted cracks and gaps). Rockwool’s range of thermal insulation products help target these weak spots, maintaining integrity to ensure you create an energy efficient structure. Developed to satisfy the latest thermal regulations, they also offer high durability, water repellence and easy handling and installation. Coupled with inherent fire, acoustic and sustainable performance you have the ultimate 4 in 1 solution.

FiRe

In-depth research has proved that the fire resistance of a timber frame building is achieved by a combination of the timber frame itself, internal lining materials and the insulation. All Rockwool insulation and firestopping products possess unrivalled inherent fire performance. Able to withstand temperatures in excess of 1000˚C, they come with a CEN fire Classification: A1 and are defined as non-combustible by the UK and Ireland building regulations. When used with the appropriate timber frame and lining products, they help ensure that your structure performs in line with current fire regulations. In conjunction with superior thermal, acoustic and sustainable performance you have the ultimate 4 in 1 solution.

02 |

coNteNtS:

Introduction 02

New Timber Frame Buildings

ToTAl BUIlDINg PERFoRmANCE 04

tHeRmAl

EXTERNAl ENVEloPE 06

ground Floors 07

External Walls 10

Pitched Roofs 12

FiRe & AcouStic

INTERNAl CoNSTRUCTIoN 14

Internal Partitions andIntermediate Floors 15

Separating Walls and Junctions 16

Separating Floors 18

tHeRmAl, FiRe & AcouStic

Refurbishment and Change of Use 20

TEchNIcAL INFORMATION

For further details visit our website at www.rockwool.co.uk

or phone the Technical Hotline on 0871 222 1780

AcouStic

modern timber frame systems possess unrivalled acoustic properties when constructed using Rockwool’s range of superior insulation products. Rockwool stone wool has an open fibrous structure, which breaks up sound waves to deliver outstanding sound absorption. Separating walls and floors and internal partitions all achieve exceptional standards to ensure you meet the latest stringent regulations. Combined with inherent thermal, fire and sustainable performance you have the ultimate 4 in 1 solution.

SuStAiNABle

The decision to construct in timber frame often stems from the desire to create an energy efficient, environmentally responsible building. Choosing the right materials is critical in realising this aspiration. Rockwool products are made from natural and sustainable diabase rock. They’re recyclable, chemically inert, free from blowing agents and rated as having zero ozone Depleting Potential. In addition, excellent thermal performance helps you to meet the government strategy of reducing the impact of development on carbon dioxide emissions. Combined with superior thermal, fire and acoustic performance you have the ultimate 4 in 1 solution.

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TOTAL BUILDING PERFORMANcE

From ground level right up to the roof, using Rockwool 4 in 1 insulation in your timber frame construction enables you to satisfy the most stringent thermal, fire, acoustic and sustainable requirements.

the versatility of rockwool insulation allows you to create the building you envisage, within your budget and construction method constraints. the outstanding performance delivered by rockwool is your assurance of the quality of the completed construction.

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tHeRmAl

01/ Ground Floor

Rockwool FlexiRockwool Rockfloor

02/ external walls

Rockwool Flexi

03/ Pitched Roofs

Rockwool RollRockwool Rockfall

FiRe & AcouStic 04/ internal Partitions and intermediate Floors

Rockwool Flexi

05/ Separating walls and Floors

Rockwool Flexi Rockwool Rockfloor Rockwool FirePro TCB Cavity Barriers

tHeRmAl, FiRe & AcouStic

06/ Refurbishment and change of use

Rockwool FlexiRockwool RockfloorRockwool Fire Barrier

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Ground Floor

external walls

Pitched Roofs

internal Partitions and intermediate Floors

Separating walls and Floors

Refurbishment and change of use

The external envelope of a timber frame building essentially comprises three elements – the ground floor, external walls and roof.

When considering the insulation of these components, the focus is on thermal performance and in particular, the key issues which must be addressed to ensure construction meets the desired standard.

06 |

EXTERNAL ENVELOPE

KEY ISSUES

Air Permeability

Air permeability is a critical factor in the energy performance of a building. Improving the air tightness will have a significant and positive affect on the overall building performance. Part l of the Building Regulations requires air permeability of 10m³ / (hr.m²). Used in conjunction with other energy saving measures such as higher levels of insulation, this will assist in delivering the required carbon emissions re-duction target under Part l. If an improved air tightness of 7m³ / (hr.m²) is achieved, less stringent U-values may be used with possible savings on insulation thickness.

cold Bridging

Cold bridging occurs when the insulation is missing in the isolating layer of the building envelope and where insulation does not butt tight together or to the adjoining structure. This can cause condensation to form and subsequent mould growth.

importance of Fit

Ensuring a perfect insulation fit is key to maintaining the thermal integrity of the external envelope. Timber containing moisture will contract as it dries out. This can result in cracks and gaps between the insulation and adjoining timber, adversely affecting air-tightness or leading to cold bridging.

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GROUND FLOORS

ground floors in timber frame construction primarily fall into two categories – ground bearing concrete and suspended timber.

ground bearing floors can be insulated above or below the concrete slab, while suspended timber floors are generally insulated between the joists.

construction and insulation methods will be determined by the designer, depending on site conditions and the required thermal performance of the floor.

For further details visit our website at www.rockwool.co.uk or phone the Technical Hotline on 0871 222 1780

08 |

GROUND FLOORS / SUSPENDED TIMBER

P10 – 240 / P10 – 250

Suspended timber FloorRockwool Flexi

Suspended timber Floor / example u-values

rockwool Flexi supported between timber joists example Floor area 5m x 8m 12m x 10mP/a ratio. 0.450 0.400 Flexi u-value u-value thickness(mm) W/m2K W/m2K 120 0.24 0.23 140 0.21 0.20 180 0.18 0.18

Supporting mesh

Ventilated airspace

to minimise air leakage, use a compressible sealant under sole plates to external walls

Ventilated Void

Suspended timber FloorRockwool Flexi

Flooring grade t&g chipboard on suspended timber floor joists with rockwool Flexi insulation between, supported by polypropylene netting with ventilated floor void below.

Rockwool Flexi

rockwool Flexi is a unique flexi-edged insulation slab developed specifically for framed constructions. the compressible edge of rockwool Flexi expands into voids created as timbers contract, ensuring a snug fit between the insulation and adjoining framework to maintain integrity.

keY BeNeFitS

• Patented Flexi edge ensures accurate fit• maintains integrity and will not slump if timbers contract• Excellent thermal properties

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GROUND FLOORS / CONCRETE GROUND BEARING

to minimise cold bridging at wall/floor junctions install 30mm rockwool rockfloor insulation at the perimeter of the concrete floor edge

to minimise air leakage, use a compressible sealant under sole plates to external walls

concrete Ground Bearing FloorRockwool Rockfloor

Sand cement or anhydrite screed on concrete floor slab on rockfloor insulation on dPM on sand blinding on hardcore.

Rockwool Rockfloor

rockwool rockfloor is a rigid, non-combustible tissue faced insulation slab with high compressive strength, developed to meet current thermal regulations. in the case of a ground bearing concrete slab, it can be placed either below or above the slab and can receive a wide range of finishes.

keY BeNeFitS

• Excellent thermal properties• High compressive resistance• Can be laid on slightly uneven surfaces

E20 – 200 / K11 – 115, 125, 135, 145 / K11 – 215, 225, 235, 245

concrete Ground Bearing Floor / example u-values rockwool rockfloor below concrete slab or screed example Floor area 5m x 8m 12m x 10m P/a ratio. 0.450 0.400

rockfloor u-value u-value thickness(mm) W/m2K W/m2K

80 0.25 0.24 115 0.20 0.20 130 0.18 0.18


rockwool rockfloor

10 |

EXTERNAL WALLS

Effective insulation of external walls has a significant impact on heat loss and energy consumption in timber frame buildings.

Rockwool Flexi

rockwool Flexi is a unique flexi-edged insulation slab developed specifically for framed constructions. the compressible edge of rockwool Flexi expands into voids created as timbers contract, ensuring a snug fit between the insulation and adjoining framework, to maintain integrity.

COLD FRAME

construction 1: Cold Frame

Standard timber frame cavity wall comprising external brickwork, 50mm cavity, breather membrane, 9mm oSB, rockwool Flexi insulation fully filling timber studs, vapour control layer and one layer of plasterboard.

construction 1: Cold Frame Standard timber frame cavity wall with rockwool Flexi insulation fully filling 140mm stud Breather membrane Standard tyvek reflex

Plasterboard layers 1 2 1 2

u - value W/m²K 0.28 0.27 0.25 0.25

Flexi thickness 140mm 140mm

imPoRtANt Note

incorporating a service void into the wall construction is the preferred option for improving air tightness and minimising damage of the vapour control layer.

in all flats and apartments, two layers of plasterboard are required internally.

Section

140mm rockwool Flexi

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EXTERNAL WALLS / COLD FRAME

construction 2: Cold Frame with Service Void

Standard timber frame cavity wall with service void comprising external brickwork, 50mm cavity, breather membrane, 9mm oSB, rockwool Flexi insulation fully filling timber studs, vapour control layer, 25mm bat-tened service void and two layers of plasterboard.

construction 2: Cold Frame with Service Void timber frame cavity wall with separate 25mm battened service void and rockwool Flexi fully filling the stud Breather membrane Standard tyvek reflex

Plasterboard layers 1 2 1 2

u-value u-value W/m2K W/m2K

Flexi 120mm 0.31 0.30 0.28 0.27 Flexi 140mm 0.27 0.26 0.24 0.24

P10 – 40, 210 , 230

minimising Air leakage and cold Bridging at external door and window Reveals

to minimise cold bridging and provide fire integrity fit

rockwool tcB cavity barrier around door and window

reveals. alternatively, for warm/hybrid constructions rockwool rock reveal can be used as a cavity barrier

to minimise air leakage flexible sealant should

be applied internally and externally to all door and

window frames and sills. it is also essential to ensure that

the vapour control layer and plasterboard is returned into

the reveal

P10 – 70 / P10 – 420 / F30 – 18 / F30 – 180

Section

rockwool tcB cavity barrier fixed with clout nails or staples

EXTERNAL DOOR AND WINDOW REVEALS

Plan

Section


Service void between battens


rockwool tcB orrock reveal cavity closer


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PITchED ROOFS

The roof structure is a key element of the external thermal envelope and can be insulated to create either ‘warm’ or ‘cold’ roof spaces.

insulating the cold roof space at horizontal ceiling level is a popular option due to the low costs involved.

however, due to higher density housing, insulation is often placed within the roof pitch to create a warm roof with additional living space.

COLD

cold Pitched Roof Rockwool Roll

roofing tiles on softwood timber battens on BBa approved breather membrane or roofing felt on timber rafters. 100mm rockwool roll fitted between the ceiling joists and 170mm rockwool roll laid over the ceiling joists will provide a u-value of 0.16 W/m²K. With 200mm rockwool roll over joists u-value will improve to 0.14 W/m²K.

Rockwool Roll

a medium density insulation mat, suitable for thermal insulation of roof spaces. the rolls have semi-perforated guidelines which enable accurate cutting of widths to suit joist spacings. this makes rockwool roll highly effective in limiting air permeability and cold bridging.

keY BeNeFitS

• multi-application product• Higher density provides excellent fit• Easy to cut to 400mm and 600mm ctrs• Excellent thermal and acoustic properties

to minimise cold bridging ensure the roof insulation overlaps the wall plate without impeding air flow

Proprietary eaves ventilator

rockwool tcB cavity barrier

P10 – 120 / P10 – 130

170mm rockwool roll over ceiling joists

100mm rockwool roll between joists

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PITchED ROOFS / WARM

K11 – 695

Rockwool Rockfall

rockwool rockfall has been specifically developed for warm roof applications where insulation is required at rafter level to create a habitable warm roof space. the system consists of rockwool high density overlay board fitted over the rafters and rockwool Flexi fitted between the rafters. as well as minimising thermal bridging rockwool rockfall is totally fire safe and provides an effective acoustic barrier against external noise pollution.

keY BeNeFitS

•Noventilationofroofspacerequired•Abreathableandvapourpermeablesystem•Reducesriskofcondensationtorooftimbers•Excellentthermalandacousticproperties•Reducesexternalnoiseingress

warm Pitched Roof - Room in RoofRockwool Rockfall

roofing tiles on softwood timber battens on BBa approved breather membrane on counter battens on rockwool rockfall overlay board on timber rafters. rockwool Flexi board is friction fitted between the rafters, underdrawn with a vapour control membrane and plasterboard.

rockwool rockfall overlay board laid staggered pattern along roof

rockwool Flexi fully filling depth of rafter

Rockfall - u-values rockwool rockfall requires the use of both the overlay and Flexi to achieve stated u-value. u-value overlay board Flexi W/m2K thickness thickness

0.20 50mm 140mm0.16 60mm 200mm


rockwool tcB cavity barrier

Vcl

The internal construction of a timber frame building gives specific regard to the internal walls and floors, including their interface with the external envelope. Internal walls and floors fall under two distinct categories. Internal partitions and intermediate floors are those within the same dwelling or living space (for example between rooms in the same dwelling or flat) while separating walls and floors refers to those dividing different dwellings (for example between semi-detached houses or flats in the same building). the Building regulations Part e in england and Wales now stipulate a minimum performance requirement for acoustic insulation in both internal walls and in floors, particularly separating, where controlling noise pollution is a key issue. Similarly, there are stringent regulations governing the effective fire performance of these elements. rockwool offer a wide range of products that can play a major part in ensuring compliance with both acoustic and fire regulations.

INTERNAL cONSTRUcTION

KEY ISSUES

minimising Flanking transmissions

Flanking sound is transmitted indirectly via paths such as service penetrations, windows, external walls and internal corridors. It is imperative that this is considered at the design stage. Specifiers should be aware that, in terms of acoustics, laboratory performance levels are difficult to achieve on site. The specified construction detailing should eliminate, or at least minimise, any downgrading of the acoustic performance. This can be achieved by gap filling, joint sealing, cavity closing and continuity of insulation to prevent sound transmission through critical junctions.

design and workmanship

When considering acoustic performance, it is of fundamental importance that good design and installation practice is maintained at all times. Crucially, all measures to eliminate or minimise flanking sound transmission should be considered at the design stage. Similarly, the builder should ensure the use of appropriate products and adherence to approved installation techniques.

Fire Performance

Fire safety requirements are based on life safety, means of escape, internal fire containment and the spread of fire from one building to another. It is essential that the stability and integrity of fire rated elements, particularly separating structures, is safeguarded. Construction methods and specification should ensure that, in the event of a fire, flame spread and smoke damage will be minimised and kept as close to the source as is practical.

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40dB internal timber Partition

the rockwool guidance specification to achieve rw 40dB consists of 63x38mm timber studs at 600mm ctrs with 50mm rockwool Flexi between the studs and one layer of 12.5mm plasterboard of 11kg/m2 mass per unit area each side (n.B. this provides 30 mins fire resistance).

keY BeNeFitS •MeetsApprovedPartEminimumsoundperformancelevel•Onlyrequires63mmdeeptimberstuds•Deliversareducedwallthickness

40dB timber Joist internal Floor

the rockwool guidance specification to achieve rw 40dB consists of standard 18mm t&g flooring grade chipboard (mass per unit area 12.4kg/m2), timber joists at 400mm ctrs with 100mm rockwool Flexi between the joists and one layer of 12.5mm plasterboard (mass per unit area 8kg/m2) underneath.

keY BeNeFitS •Allowsuseofstandard12.5mmplasterboardceiling• Standard18mmchipboardflooring•Reducedfloorweight•Unlikerollproducts,RockwoolFlexicanbefittedfrombelow

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INTERNAL PARTITIONS AND INTERMEDIATE FLOORS

meeting Approved Document Part E the new approved document e (2003 edition) introduces, for the first time, performance criteria for internal walls and floors (those within the same dwelling).

this is based on laboratory rating (rw) for which a minimum value for airborne sound insulation of rw 40dB is required.

P10 – 230 P10 – 240


50mm rockwool Flexibetween studs

100mm rockwool Flexi between floor joists

timber Separating wall Robust details Reference E-WT-1

to consist of two independent timber stud frames with a minimum 50mm gap between and a minimum of 240mm between inner faces of wall linings, to consist of two or more layers of gypsum based plasterboard (total nominal mass per unit area to be 22kg/m2). Fit a minimum 60mm rockwool Flexi to both frames.

Part e england and Wales: Separating Wallsnew build performance requirement: airborne Sound dntw + ctr = 45dB (or greater).

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SEPARATING WALLS AND JUNcTIONS

Rockwool Flexi rockwool Flexi is a unique flexi-edged insulation slab developed specifically for framed constructions and offers excellent acoustic properties. the compressible edge maintains acoustic integrity by ensuring a snug fit between the insulation and supporting studs.

keY BeNeFitS • PatentedFlexiedgeensuresaccuratefit•Maintainsacousticintegrityandwillnotslumpiftimbercontracts• Excellentacousticproperties

Rockwool Firepro tcB cavity Barriers Firepro tcB cavity Barriers comprise a strip of rockwool encapsulated in a protective polyethylene sleeve. the tcB range has been specifically designed and tested to reduce the risk of fire spread in timber framed constructions.

keY BeNeFitS

•MeetsUKandIrelandbuildingregulations•Maintenancefree•Waterrepellent• Easyhandlingandfitting•Firetestedandassessedbyaccreditedthirdparty•Providesupto60minutesfireintegrityandinsulation•Backedbyfiretestinformation

P10 – 40 / P10 – 210 / P10 – 230

60mm rockwool Flexibetween each frame

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P10 – 70 & 420 / P10 – 40, 210, 230

SEPARATING WALLS AND JUNcTIONS

P10 – 40, 70, 210, 230, 240, 250, 420 / K10 – 695 / K12 – 250

Pitched Roof Separating wall JunctionRoom in Roof

the separating wall lining in the roof space is to consist of two or more layers of gypsum plasterboard (min 22kg/m2 both sides) with all joints staggered. the separating wall is to continue to the underside of the roof structure with junction between filled with rockwool Flexi a minimum of 300mm wide.

external wall / Separating wall Flanking and Firestopping detail rockwool Flexi located within the separating wall and external wall studs with rockwool tcB cavity barriers fitted vertically at wall junctions and horizontally at separating floor junctions. external wall to receive two layers of plasterboard (each min. 10kg/m2) where there is a separating floor above or below.

rockwool tcB cavity barriers compression fitted between outer leaf and timber frame. rockwool tcBs meet the generic requirement of Part e robust details, requiring the use of cavity closers to reduce flanking transmission along external masonry / separating cavity walls

Seal all plasterboard joints with tape or caulk with rockwool acoustic Sealant

Separating wall

Junctions between separating walls and roofs should be firestopped to the underside of the tiling to prevent flame spread between dwellings. in addition a cavity barrier should be provided within boxed eaves. rockwool timber Frame Wired Mat can be fixed to both sides of the rafter and carefully cut to shape to fully seal the boxed eaves

over separating walls fit 30mm rockwool rWa45 slab between tiling battens

60mm rockwool Flexi insulation is required in the separating wall section above the ceiling where there is a room in the roof


SectionPlan

tile batten space

rockwool tcB cavity Barrier at floor junctions


rockwool Flexi between rafters

60mm rockwool Flexi

60mm rockwool Flexi

construction 1: Platform Floor(Pre-completion testing required)

Airborne: Rw 54dB (Rw 66 - 12 ctr)impact: lnw 54dBlab test report: l03 272 & 273

18mm t&g flooring grade chipboard on 15mm gypsum based plasterboard (13kg/m2) on 50mm rockwool rockfloor resilient layer on 15mm oSB on 200x50mm timber joists at 400mm ctrs with 100mm rockwool Flexi between joists, 16mm minimum resilient bars fixed at 400mm ctrs perpendicular to joist span with ceiling finish of 2 layers of 15mm gypsum based plasterboard (26kg/m2).

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SEPARATING FLOORS

P10 – 240, 250 & 420 / K11 – 215, 225 & 235 /K20 – 150 & 160

Rockwool Rockfloor

rockwool rockfloor is a rigid, non-combustible tissue faced insulation slab with high compressive strength. it has been developed to help ensure you meet the current stringent acoustic regulations.

keY BeNeFitS •Excellentacousticproperties•Highcompressiveresistance•Designedforusebelowmostfloorfinishes•Canbelaidonslightlyunevensurfaces

Part e england and Wales: Separating Floorsnew build performance requirement: airborne Sound dntw + ctr = 45dB (or greater)impact Sound lntw = 62dB (or less).

imPoRtANt Note

rockwool rockfloor of thickness 50mm can be recessed to receive services, providing a minimum thickness of 20mm rockfloor is maintained between the services and the sub-floor deck. to ensure accurate recess cutting, a rockwool ‘Shark’ tool should be used.

P10 – 240, 250 & 420 / K11 – 215, 225 & 235 /K20 – 150 & 160

construction 2: Platform Floor with recessed downlighters(Pre-completion testing required)

Airborne: Rw 53dB (Rw 65 - 12 ctr)impact: lnw 54dB lab test report: l03 274 & 275

Floor as construction 1 (Platform Floor) with ceiling finish of 2 layers of 15mm gypsum based plasterboard (26kg/m2) with tenmat FF 109 downlighter covers and aspect lighting downlights (1 per 1.8m2).

100mm rockwool Flexi between joists 100mm rockwool Flexi between joists

50mm rockwool rockfloor 50mm rockwool rockfloor

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external wall / Separating Floor Junctionrobust detail e-Ft-1

Floating floor treatment for e-Ft-1 to consist of 18mm (minimum) t&g flooring board on gypsum based board (nominal 13.5kg/m2) on FFt-1 resilient composite deep battens a minimum of 70mm deep (resilient layer at top or bottom) and 25mm rockwool acoustic slab between the battens, ensuring any services do not penetrate the resilient layer.

SEPARATING FLOORS

imPoRtANt Note

to reduce flanking noise, floors should be isolated from the perimeter walls. it is crucial that the floating layer and base floor are not bridged by services or fixings that penetrate the resilient layer. a minimum 5mm gap should be maintained between the floating layer and skirtings, with gaps sealed using rockwool acoustic Sealant. in addition, all ceiling perimeters should be sealed with tape or rockwool acoustic Sealant.

P10 – 70 & 420 / P10 – 40, 210, 230P10 – 40, 210, 230, 240, 250 / K10 – 695 / K12 – 250

Separating wall / Separating Floor Junctionrobust detail e-Ft-1

ceiling treatment consists of 16mm deep (minimum) resilient bars fixed to joist at 400mm ctrs perpendicular to joist span with two layers of gypsum based board composed of one layer of 19mm (nominal 13.5kg/m2) fixed to bars with 32mm screws and one layer of 12.5mm (nominal 10kg/m2) fixed with 42mm screws. to avoid flanking transmission ensure ceiling boards have staggered joints, service cables are sealed with flexible sealant, and screws do not penetrate joists.

5mm (minimum) resilient isolating strip

close length of cavity with rockwool tcB cavity closers

240mm (minimum) deep timber i joists


close length of cavity with rockwool tcB cavity closersat floor junctions

5mm (minimum) resilient isolating strip


240mm (minimum) deep timber i joists with 100mm rockwool Flexi between the joists

Wall finish

two layers of gypsum based plasterboard fixed both sides, of nominal mass per unit area 22kg/m², laid with staggered joints

100mm Flexi

60mm Flexi in each frame

25mm rockwool acoustic Slab

140mm Flexi

rockwool acoustic Slab

100mm Flexi


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When considering any refurbishment work or conversions to existing properties in order to create more space, there are a number of important issues that need to be taken into account. Current building regulations stipulate certain performance standards that need to be adhered to and it is important that these standards are achieved throughout the specification and construction stages.

acoustic performance, fire safety and thermal efficiency are all of paramount importance. Because the extent of conversion work will vary with each project, the developer is advised to consult with the local building control officer prior to commencement of any works on site.

REFURBIShMENT AND chANGE OF USE

KEY ISSUES

Fire and Acoustics

refer to internal construction

thermal

refer to external envelope

Acoustic upgrade of existing internal masonry wall to create Separating wall(Pre-completion testing required)

When upgrading acoustic performance of an existing internal masonry wall to form separating wall (also for room in roof method), a minimum airborne sound reduction of dntw + ctr of 43dB (or greater) is required.

adopt following construction: 100mm (min) existing solid masonry wall plastered on both faces, independent timber or steel studs (minimum 10mm gap to be maintained between frame and existing wall), 50mm rockwool Flexi between studs, two layers of plasterboard min 20 kg/m2 (approx = to 2 x 15mm wallboard or 2 x 12.5mm layers of acoustic plasterboard).

to avoiding flanking transmission, seal perimeter edges of new plasterboard with tape or rockwool acoustic Sealant.

imPoRtANt Note if existing masonry wall is not plastered or less than 100mm thick then wall treatment should be applied to both sides.

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K10 – 35, 115, 125, 155, 165 / K12 – 330

Rockwool Flexi

rockwool Flexi is a unique flexi-edged insulation slab developed specifically for framed constructions. the compressible edge ensures a snug fit between the insulation and adjoining framework, maintaining integrity.

keY BeNeFitS • PatentedFlexiedgeensuresaccuratefit•Maintainsintegrityandwillnotslumpiftimberscontract•Excellentthermalandacousticproperties•CENfireClassification:A1•Ratedasnon-combustibleinUKandIrelandbuildingregulations•Fullysustainable,recyclableproduct•Easyhandlingandfitting

Section

10mm gap between frame and wall

50mm Flexi between timbers


Rockwool Fire Barrier rockwool Fire Barriers are capable of achieving both integrity and insulation protection periods from 15 to 120 minutes.

keY BeNeFitS

•Noboltsrequired•Standardno.10woodscrewsfortimber•Fixingsforclampingplateextendedto450mm•Speedofinstallationincreased•Costsofinstallationreduced

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one Hour compartmentation in Roof Space (non-habitable)

Rockwool Fire Barrier

Fire barrier systems are required to prevent flame, heat and smoke spread within buildings. Specification of the correct products and installation methods are paramount in preventing fire spread to adjacent areas (rockwool Fire Barriers also provide the added benefit of contributing to a reduction in flanking noise).

K10 – 82, K12 – 330

imPoRtANt Note

When fixing rockwool Fire Barrier to timber (for example trussed rafters) with a thickness of 35-49mm, one layer of 60mm rockwool Fire barrier must be fixed either side to achieve one hour integrity. For timber with a thickness of 50mm or greater, the thickness of the fire barrier can be reduced to 50mm, with no loss of performance.

Fill space between battens with 300mm wide x 30mm thick rWa45

rW clamping Plates fixed with no.10 wood screws at 450mm ctrs

35mm thick timber trussed rafter

60mm rockwool Fire Barrier tightly butt jointed and stitched

50mm Flexi between timbers

See page 21 for upgrading existing wall construction.

New external dormer walls – cold Frame

dormers are often constructed to offer additional space when creating a room in the roof.

dormer walls constructed in tile/slate hanging, treated tiling battens, breather membrane, 12mm oSB sheathing, rockwool Flexi insulation fully filling timber studs, vapour control layer and one layer of plasterboard

rockwool Flexi between studs only rockwool Flexi u-value thickness (mm) W/m2K

120mm 0.35140mm 0.29

| 23For further details visit our website at www.rockwool.co.uk or phone the Technical Hotline on 0871 222 1780


P10 – 240, 250, 420 / K11 – 215, 225, 235 / K20 – 150, 160

existing timber Floor – Upgraded to one Hour Fire Resistance

remove existing floor finish and lay 25mm diameter wire mesh over existing ceiling, stapled to sides of joists.

lay 100mm rockwool Flexi between joists, supported by wire mesh.

P10 – 240, 250

existing floor joists minimum size 195x45mm at 400 ctrs

existing lath and plaster ceiling may be retained if in good order. Boards with a layer of 3mm hardboard above or below

existing timber Floor – upgraded to Separating Floor status(Pre-completion testing required)

Airborne dntw + ctr = 43dB (or greater)impact lntw = 64dB (or less)

Floor to consist of a minimum two layers of board material spot bonded together with joints staggered to provide minimum total mass 25kg/m2. 25mm (minimum), rockwool rockfloor resilient layer laid on existing floor deck and 100mm rockwool Flexi to be laid between floor joists.

existing ceiling should be upgraded to 20kg/m2 (n.B. if existing ceiling is lath and plaster it should be retained providing it satisfies Part B – Fire Safety. if in doubt underdraw existing ceiling layer in an additional layer of 12.5mm plasterboard screwed into joists).

Rockwool Rockfloor

rockwool rockfloor is a rigid, non-combustible tissue faced insulation slab with high compressive strength. it has been developed to help ensure you meet the current stringent acoustic regulations.

keY BeNeFitS •Excellentacousticproperties•Highcompressiveresistance•Designedforusebelowmostfloorfinishes•Canbelaidonslightlyunevensurfaces

Minimum 25mm rockfloor

100mm Flexi

100mm Flexi

Floor to receive new floor finish either 18mm t&g chipboard or square edged board with a layer of 3mm hard board

Rockwool limited: Pencoed, Bridgend, South WaleS cF35 6nY

t: 01656 862621 F: 01656 862302 W: www.Rockwool.co.uk

FoR FuRtHeR detAilS ANd tecHNicAl iNFoRmAtioN ViSit:

www.Rockwool.co.uk or call 0871 222 1780

Printed on recycled paper. 2008 editioN.

Documents

TIMBER FRAME - Encon Insulation · specifically for framed constructions. the compressible edge of rockwool Flexi expands into voids ... and energy consumption in timber frame buildings