CI/SfB (4-) Rf9 January Dry fix and ventilation systems including UNIVERSAL accessories. Roofing product catalogue 45

Transcription

1 CI/SfB (4-) Rf9 January 2016 Dry fix and ventilation systems including UNIVERSAL accessories Roofing product catalogue 45

2 Today s roofs need to be weatherproof and look good, as well as providing adequate ventilation. For you, they also need to be quick and economical to install, and for the building owner they require minimal on-going maintenance but maximum durability and long life. Marley Eternit offer all this, as well as NHBC approved tile fixing and mortar bedding options that make it easy for you to comply with BS Let ME lighten your load Trust Marley Eternit to take the hassle out of roofing. If you ever need advice on any roofing related issue, you can rely on our team to give you a helping hand. Call on at info@marleyeternit.co.uk Or visit All factories certified to ISO 9001, ISO 14001, OHSAS Introduction

3 Contents 2-3 Introduction 4-5 Ventilation and dry fix systems 6-7 Ventilation and dry fix system selector 8-9 Eaves vent systems Verge systems Ridge systems 21 Abutment system Hip systems Valley systems Roof slope ventilation Cold roof ventilation requirements Warm roof ventilation requirements Technical toolkit, services, sustainability and standards Introduction 3

4 Ventilation and dry fix systems Eaves vent systems 02 Dry verge systems 10mm and 25mm UNIVERSAL eaves vent systems (pages 8-9) UNIVERSAL dry verge system (pages 10-11) Continuous dry verge system (pages 12-13) Cloak verges (pages 14-15) 03 Dry ridge systems UNIVERSAL RidgeFast system (pages 16-17) Ventilated dry ridge system (pages 18-19) Ventilated dry mono-ridge system (pages 18-19) UNIVERSAL ridge roll (page 20) 4 Ventilation and dry fix systems

5 04 Abutments 05 Dry hip systems 06 Dry valley systems Top abutment ventilation system (page 21) UNIVERSAL HipFast system (pages 22-23) Dry hip system (pages 24-25) UNIVERSAL GRP dry valley system (pages 26-27) GRP slate dry valley system (page 28) 07 Roof slope systems 08 Ridge vent terminals UNIVERSAL tile vent terminal (page 29) Contour and in-line vents (pages 30-33) Tile ventilation terminals (pages 34-35) Ridge vent and gas ridge vent terminals (pages 36-37) The Universal ranges offer you a 'system in a box' complete with dry fix and ventilation solutions suitable for all Marley Eternit roofing products and with other manufacturers tiles and slates. Ventilation and dry fix systems 5

6 Ventilation and dry fix system selector Tile Concrete Clay Fibre Melodie Maxima plain plain cement slates UNIVERSAL roofing accessories 10mm eaves vent system 25mm eaves vent system Dry verge HipFast RidgeFast Ridge Roll Dry valley Tile vent Dry verge Cloak verge system Edgemere dry verge Plain tile dry verge Slate verge trim Dry hip Dry hip system Dry hip with duo pitch ridges Dry valley Plain tile valley GRP interlocking slate dry valley system Ventilated dry ridge Ventilated dry ridge Ventilated dry mono ridge Fibre cement ventilated ridges Ventilation terminals Gas vent ridge terminals Ridge vent terminals In-line vents Tile vent terminals * Modern only 6 Ventilation and dry fix system selector

7 Edgemere Ashmore Ludlow Anglia Double Ludlow EcoLogic Mendip Wessex Modern & range Plus Roman Major Ludlow Duo Modern Major * Ventilation and dry fix system selector 7

8 eaves vent systems For use with all tiles and slates 25mm eaves vent system Find out more about this product by scanning the QR code or visit: marleyeternit.co.uk/eavesvent Advantages > Can be used with all Marley Eternit and other manufacturers tiles and slates > Simple and fast to install > Eaves-to-ridge or eaves-to-eaves ventilation > pitched roofs > Allows clip fixing of tiles at eaves > Compresses insulation ensuring airflow > Prevents ponding of water > Prevents ingress of birds, vermin and insects 8 Eaves vent systems

9 Key components Universal 10mm eaves vent system (6m pack) Pack comprises of: Eaves rafter roll (6m) Universal 25mm eaves vent system (6m pack) Pack comprises of: Eaves rafter roll (6m) Felt support tray (10 No.) Felt support tray (10 No.) 10mm strip ventilator (6 No.) 25mm strip ventilator (6 No.) Also available: Also available: Comb filler strip Gutter spacers (20 per pack) Continuous rafter roll pack (2 No. 6m) Fixing overview Nailing strip ventilator onto fascia board Place felt support trays over vent strips and nail to rafters Underlay over support tray (stop 25mm from curved edge) When using profiled tiles, fix comb filler strip to fascia Find out more... > Sitework guide for fixing instructions > marleyeternit.co.uk/resources > tel Eaves vent systems 9

10 For use with large format concrete interlocking tiles dry verge systems Find out more about this product by scanning the QR code or visit: marleyeternit.co.uk/dryverge For Marley Eternit dry fix roofing systems Advantages > Meets BS 5534 requirements and NHBC guidelines > Strong and durable > Weathertight and maintenance free > Mechanically fixed > Emulates appearance of traditional verge > Simple and fast to install > Also suitable for verges without bargeboard > Dry verge refurbishment kit allows retro-fit to existing verges 10 Verge systems

11 Key components Verge unit left hand 391* right hand 392* ( mm gauge, mm lap) Edgemere verge unit left hand 381 right hand 382 ( mm gauge, mm lap) Modern ridge end cap 394* Modern mono-ridge end cap left hand 408* right hand 409* Segmental mono-ridge end cap left hand 427* right hand 428* Dry verge refurbishment kit (to fix 24 units) Segmental ridge end cap 395* Edgemere ridge end cap 384 Dry verge fixing kit (to fix 28 units) Edgemere dry verge fixing kit (to fix 28 units) * Suffix with colour code: 01 Grey, 03 Brown, 04 Terracotta Suffix with colour code: 01 Grey, 03 Brown Fixing overview Slide up each unit to interlock Mono-ridge end cap with fixing Screw fix ridge end cap Batten extension unit; part of dry verge refurbishment kit Find out more... > Sitework guide for fixing instructions > marleyeternit.co.uk/resources > tel Verge systems 11

12 Continuous dry verge systems For use with fibre cement slates, Ashmore interlocking tiles, concrete plain tiles and clay plain tiles Fibre cement slates verge trim Key component Fibre cement slates verge trim (3m) MA42206 Advantages > Meets BS 5534 requirements and NHBC guidelines > Strong and durable > Weathertight and maintenance free > Creates continuous clean verge detail 12 Verge systems

13 Key components Universal plain tile dry verge Verge section (3m) * one kit per length of verge Plain tile dry verge fixing kit* Universal Plain tile dry verge Fixing overview Nail Slate Verge Trim through flange into battens Slate Verge Trims intersecting at ridge Universal plain tile verge connector units Installed dry verge system Find out more... > Sitework guide for fixing instructions > marleyeternit.co.uk/resources > tel Verge systems 13

14 Cloak verges For use with clay and concrete plain tiles, Mendip, Modern and Double Roman interlocking tiles Mendip interlocking tile cloak verge Plain tile cloak verge Advantages > Meets BS 5534 requirements and NHBC guidelines > Strong and durable > Weathertight and maintenance free > Suitable with or without bargeboard > Creates continuous, clean verge > Suitable for range of laps > Maximum pitch of 55 if top tile mitred > Colour matched to main tiles 14 Verge systems

15 Key components Mendip cloak verge left hand 245 right hand 246 Modern cloak verge left hand 370 right hand 371 Mendip half tile 247 Modern half tile 372 Mendip fixing kit Double Roman cloak verge left hand 265 right hand 266 Modern fixing kit Concrete plain tile cloak verge left hand 249 right hand 250 Double Roman half tile 102 Double Roman fixing kit Clay plain tile cloak verge left hand right hand Fixing overview Completing interlocking profiled tile cloak verge at ridge Maintaining broken bond with half tiles for Modern cloak verge Stop end ridge tile used to finish clay plain tile cloak verge at ridge Concrete block end ridge finishing plain concrete cloak verge tiles Find out more... > Sitework guide for fixing instructions > marleyeternit.co.uk/resources > tel Verge systems 15

16 RidgeFast system For use with all tiles and slates Find out more about this product by scanning the QR code or visit: marleyeternit.co.uk/ridgefast Advantages > Meets BS 5534 requirements and NHBC guidelines > Simple and fast to install > Can be used with all Marley Eternit and other manufacturers tiles and slates > Completely dry fixed system > Suitable with standard ridge tiles > Provides 5mm continuous ventilation along the ridge 16 Ridge systems

17 Key components Universal RidgeFast system (6m pack) Pack comprises of: Ridge roll (6m) RidgeFast blanking tape (2 x 2m) RidgeFast/HipFast union pack (6 No. unions) Ridge batten brackets (10 No.) Ridge unions (13 No.) Fixing overview Roll out RidgeFast roll Using ridge roll applicator Lay and fix ridges onto roll Secure ridge union Find out more... > Sitework guide for fixing instructions > marleyeternit.co.uk/resources > tel Ridge systems 17

18 Ventilated dry ridge system For use with all concrete tiles and fibre cement slates Dry ridge system For Marley Eternit dry fix roofing systems Dry mono-ridge system Advantages > Meets BS 5534 requirements and NHBC guidelines > Simple and fast to install > Weathertight and maintenance free > Can be used up to 55º pitch > Provides 5mm continuous ventilation along the ridge > Can be used with all fibre cement slates, concrete tiles and slates > Fully compatible with dry hip system 18 Ridge systems

19 Key components Batten sections (3m) Plain tile High profile Low profile Steep pitch batten sections (45-55 ) (3m) High profile Low profile Segmental ridge junction apex cap 439* Modern ridge junction apex cap 440* Modern ridge union 414* Segmental ridge union 413* Segmental mono-ridge union 423* Segmental mono-ridge end cap left hand 427* right hand 428* Filler units Double Roman vented Ludlow Major vented Ludlow Plus vented Mendip vented Wessex vented Anglia vented Plain/Modern/Edgemere/ Ashmore vented Dry ridge top course clip and nail pack Modern/Duo Modern Edgemere/Duo Edgemere * Suffix with colour code: 01 Grey, 03 Brown, 04 Terracotta Fixing overview Slit underlay between batten sections and clip using H section piece Fixing ridge end cap to dry ridge battens Clip top course interlocking tiles or slates (tiles shown) Fix ridge units and unions Find out more... > Sitework guide for fixing instructions > marleyeternit.co.uk/resources > tel For Double Roman, Mendip, Wessex and Anglia For Ashmore, Edgemere range, Modern, Duo Modern, Ludlow Plus, Ludlow Major and fibre cement slates Ridge systems 19

20 For use with fibre cement slates and ridges ridge roll Key components Fixing overview Universal ridge roll Fibre cement ventilated dry ridges Duo pitch ridge Stop end for duo pitch ridge Ridge roll with ridges 60mm x 14 gauge self-sealing screws Advantages > Simple and fast to install > Maintenance free > Can be used for ridges and hips > Completely dry fixed system > Provides 5mm continuous ventilation along the ridge > Pitch range 15 to 60º Find out more... > Sitework guide for fixing instructions > marleyeternit.co.uk/resources > tel Ridge systems

21 Top abutment ventilation system For use with all concrete tiles, clay plain tiles and fibre cement slates Fixing overview Insertion of profiled tiles into batten section Finish by dressing lead onto lead support strips Key components Batten sections (3m) Plain tile High profile Low profile Steep pitch batten sections (45-55 ) (3m) High profile Low profile Lead support strip Fixing kit (6m) Filler units Double Roman vented Ludlow Major vented Ludlow Plus vented Mendip vented Wessex vented Anglia vented Plain/Modern/Edgemere/ Ashmore vented Advantages > Provides ventilation for lean-to roofs > Completely dry fixed > Provides continuous 5mm ventilation along abutment > Provides eaves-to-abutment ventilation when used with universal eaves system Find out more... > Sitework guide for fixing instructions > marleyeternit.co.uk/resources > tel For Double Roman, Mendip, Wessex and Anglia For Ashmore, Edgemere range, Modern, Duo Modern, Ludlow Plus, Ludlow Major and fibre cement slates Abutment systems 21

22 HipFast system For use with all tiles and slates Find out more about this product by scanning the QR code or visit: marleyeternit.co.uk/hipfast Advantages > Meets BS 5534 requirements and NHBC guidelines > Simple and fast to install > Can be used with all Marley Eternit and other manufacturers tiles and slates > Completely dry fixed system > Suitable for standard hip tiles 22 Hip systems

23 Key components Universal HipFast system (6m pack) Pack comprises of: Hip roll (6m) Hip batten brackets (6 No.) Tapered ridge filler (2 No.)* 1m length hip support trays** mm each (9 No.) RidgeFast/HipFast union pack (6 No. unions) * For use with Modern ridge tiles only ** Sold separately Ridge unions (13 No.) Fixing overview Fixing hip batten brackets Fixing hip batten Roll out HipFast roll Fixing hip unions Find out more... > Sitework guide for fixing instructions > marleyeternit.co.uk/resources > tel Hip systems 23

24 Dry hip system For use with all concrete tiles For Marley Eternit dry fix roofing systems Advantages > Meets BS 5534 requirements and NHBC guidelines > Simple fast installation > Weathertight and maintenance free > Can be used up to 55 pitch > Can be used with all Marley Eternit concrete tiles > Fully compatible with ventilated dry ridge system 24 Hip systems

25 Key components Dry hip batten section (low profile) Modern ridge union 4140* Dry hip batten section (high profile) Dry hip batten section fixing kit (1 kit per 3 metre batten section) Low profile High profile Modern stop end hip tile 292 Modern hip apex cap * * * Third round stop end hip tile 291 Third round ridge union 4140* Third round hip apex cap * * * * Suffix with colour code: 1 Grey, 3 Brown, 4 Terracotta Fixing overview Locate hip batten section between cut tiles Insert closed cell foam rubber slip at hip/ridge junction Locate block end hip tile and assembly Secure apex junction cap with hip/ridge unions Find out more... > Sitework guide for fixing instructions > marleyeternit.co.uk/resources > tel Hip systems 25

26 For use with all concrete plain and interlocking tiles GRP dry valley For Marley Eternit GRP valley trough flashings Advantages > Dry fix, mortar-free system > Durable GRP technology > Simple and fast installation > Can accommodate up to 20 pitch variance either side of valley > Performs on pitches up to 60 > Gives the appearance of a close cut roof 26 Valley systems

27 Key components GRP valley (low profile) GRP valley (high profile) Tile tail clips (pack) Head clips (pack) Compatibility High profile Ashmore Anglia Double Roman Edgemere/Duo Edgemere Ludlow Major Ludlow Plus Mendip Modern/Duo Modern Wessex Plain Low profile Fixing overview Valley board construction Placement and fixing of valley trough Tiles or slates cut to rake of valley Find out more... > Sitework guide for fixing instructions > marleyeternit.co.uk/resources > tel Valley systems 27

28 GRP slate valley systems For use with fibre cement slates Key components Fixing overview GRP slate dry valley trough (22.5 to 40 ) Clipped, raking cut interlocking slates laid with GRP valley trough Advantages > Dry fix, mortar free system > Durable GRP technology > Simple and fast installation > Accommodates up to 15 pitch variance either side of the valley Find out more... > Sitework guide for fixing instructions > marleyeternit.co.uk/resources > tel Valley systems

29 tile vent terminal For use with large format interlocking tiles Key components Universal tile vent terminal Grey Brown Terracotta Flexible pipe* ID 110mm (sold separately) Find out more about this product by scanning the QR code or visit: marleyeternit.co.uk/tilevent Fixing overview Pressure resistance values Pa (litres/sec airflow) ,000mm 2 free area Ensuring good seal between Universal tile vent terminal and tiles Finishing tiling and creating a weatherproof seal Advantages > Ideal for natural, mechanical or soil pipe ventilation > Weatherproof, tough and durable > Suitable for large format and most 15 x 9 interlocking tiles > 15,000mm 2 free area of ventilation > Choice of 3 colours Find out more... > Sitework guide for fixing instructions > marleyeternit.co.uk/resources > tel * Universal tile vent terminal must be used in conjunction with flexible pipe only. Roof slope systems 29

30 Contour in-line vents For use with all plain tiles and concrete interlocking tiles For Marley Eternit contour tile vent terminals Pressure resistance values Tile Free area of Pa (l/s airflow) ventilation (mm 2 ) Anglia 15, Ashmore 10, Double Roman 13, Edgemere 10, Ludlow Major 11, Tile Free area of Pa (l/s airflow) ventilation (mm 2 ) Ludlow Plus 15, Mendip 14, Modern 10, Plain 10, Wessex 12, Advantages > Contoured to match tile profile > Almost invisible from ground level > Ideal for mid slope roof ventilation > Internal spigot for connection to mechanical extract or soil pipe ventilation 30 Roof slope systems

31 Key components Plain contour tile vent 455* terminal Ludlow Major contour tile 456* vent terminal Edgemere contour tile vent 465* terminal Ludlow Plus contour tile 457* vent terminal Mendip contour tile vent 452* terminal Double Roman contour tile 453* vent terminal Modern contour tile vent 451* terminal Ashmore contour tile vent 450 terminal Anglia contour tile vent 460* terminal Flexible pipe ID 110mm (sold separately) Wessex contour tile vent 459* terminal * Available in grey and brown Fixing overview Make aperture in underlay using template Secure soaker tray Find out more... > Sitework guide for fixing instructions > marleyeternit.co.uk/resources > tel Contour vents have a minimum pitch of 22.5 Roof slope systems 31

32 Clay in-line vent For use with clay plain tiles Key components Clay in-line tile vent Fixing overview CUT 340mm In-line tile vent adaptor Mark throat position and cut underlay Position and fix in-line vent unit Flexible pipe ID 110mm (sold separately) Pressure resistance values Pa (litres/sec airflow) ,500mm 2 free area Advantages > Real clay tile slips provide visual integration on roof slope > 7,500mm 2 free area of ventilation > Ideal for natural, mechanical or soil pipe ventilation Find out more... > Sitework guide for fixing instructions > marleyeternit.co.uk/resources > tel Roof slope systems

33 Fibre cement in-line vent For use with fibre cement slates Key components In-line slate vent Fixing overview Additional support batten 280mm cut between battens In-line fibre cement/natural PVCu slate ventilator Secure additional support batten Determine position of ventilator Flexible pipe ID 110mm (sold separately) Pressure resistance values Pa (litres/sec airflow) ,000mm 2 free area Advantages > Provides visual integration with roof slope > Ideal for natural, mechanical or soil pipe ventilation > 10,000mm 2 free area of ventilation Find out more... > Sitework guide for fixing instructions > marleyeternit.co.uk/resources > tel Fibre cement in-line vent has a minimum pitch of 20 Roof slope systems 33

34 Tile ventilation terminals For use with large format concrete interlocking tiles including Ashmore Advantages > Wide range of colours and finishes > Ideal for natural, mechanical or soil pipe ventilation 34 Roof slope systems

35 Key components Edgemere tile vent terminal 259 Double Roman tile vent 298 terminal Ludlow Major tile vent 297 terminal Wessex tile vent terminal 294 Mendip tile vent terminal 294 Flexible pipe ID 110mm (sold separately) Modern/Duo Modern 295 tile vent terminal Ashmore ventilation roof tile 263 (for natural ventilation only) Fixing overview Pressure resistance values Make aperture in underlay using template Secure soaker tray Tile Free area of Pa (l/s airflow) ventilation (mm 2 ) Ashmore 4,500 Double Roman 7, Edgemere 7, Ludlow Major 7, Mendip 7, Modern 7, Wessex 6, Find out more... > Sitework guide for fixing instructions > marleyeternit.co.uk/resources > tel Roof slope systems 35

36 Ridge vent terminals Available to suit concrete and fibre cement ridges Advantages > Suitable for mechanical or passive stack ventilation > Compatible with our range of ventilated dry ridge systems > Simple and fast installation 36 Roof slope systems

37 Key components For concrete tiles and slates Ridge vent terminal 198 Also available: Gas vent ridge terminals for concrete tiles and slates Gas vent ridge terminal 256 (with extension piece) Plumbers accessory pack (for ridge vent terminals only) Spare gasket set For fibre cement slates In-line ridge ventilator plus extension sleeve (900mm) 20, 25, 30, 35, 40, 45 In-line ridge ventilator stepped adaptor Gas vent ridge flue terminal for condensing boilers Segmental 254* Modern 255* Modern/segmental Adaptor ridge union 420** * Made to order Flexible pipe ID 110mm (sold separately) Fixing overview Installation of gas vent ridge terminal (with flexible pipe) Find out more... > Sitework guide for fixing instructions > marleyeternit.co.uk/resources > tel Roof slope systems 37

38 Cold roof ventilation requirements Key to illustrations Warm roof/building areas Cold roof areas Low Resistance underlay High Resistance underlay Sarking Normal ceiling A ceiling where no attempt has been made to seal all gaps or penetrations (e.g. light drops, pipes etc.) Well sealed ceiling The design avoids construction gaps, especially at the wall ceiling junction with dry lining construction and holes in the ceiling. No access door or hatch should be located in rooms where large amounts of moisture are produced, including kitchens or bathrooms. The ceiling is sealed to the external walls to limit any leakage through cracks. The head of all cavities in the external walls, party walls and partition walls is sealed to prevent transfer of warm moist air into the loft. Roofs with a well-sealed ceiling Bituminous felts and vapour impermeable underlays (high resistance) The ventilation requirements for cold roofs with vapour impermeable underlays and 'well-sealed ceilings' are the same as for those without. Installing a 'well-sealed ceiling' will make the roof more energy efficient because airtightness will have prevented heat loss through convection. Heat loss due to low speed air currents over the cold side of the insulation (caused by ventilation) is negligible. Vapour permeable underlays (low resistance) The installation and maintenance of a 'well-sealed ceiling' with a vapour permeable underlay can reduce the ventilation requirements. However, where a close fitting roof covering is used, the batten space should be ventilated in accordance with BS 5250: 2011 using counterbattens. 10,000 10,000 mm 2 /m 3,000 3,000 mm 2 /m Well-sealed ceiling Well-sealed ceiling Roof spans under 10m (pitches under 35 ) Roof spans under 10m (pitches of ) 5,000 mm 2 /m 5,000 mm 2 /m 10,000 mm 2 /m 10,000 mm 2 /m 3,000 mm /m 3,000 mm /m Normal ceiling Well-sealed ceiling Roof spans over 10m (or pitches over 35 ) Roof spans over 10m (or pitches over 35 ) 38 Cold roof ventilation requirements

39 Roofs with a normal ceiling Bituminous felts and vapour impermeable underlays (high resistance) Ventilation of the loft space under a traditional bituminous felt or non-vapour permeable underlay has proven to be an effective and robust solution when used with suitable high and low level ventilation. 10,000 mm /m mm /m 10, Vapour permeable underlays (low resistance) The use of a low resistance underlay can reduce the requirement for ventilating the roof space. On fully boarded roofs, i.e. sarking, low resistance underlays should be treated as impermeable and the roof space below ventilated in accordance with the high resistance underlay requirements described above. Where a close-fitting roof covering has been used, the batten spacing should be ventilated in accordance with BS 5250: 2011 using counterbattens. Normal ceiling Roof spans under 10m (pitches under 35 ) 5,000 mm /m 2 7,000 Normal ceiling 7,000 10,000 mm /m 2 10,000 mm /m 2 Roof spans under 10m (pitches under 35 ) Normal ceiling 5,000 Roof spans over 10m (or pitches over 35 ) 7,000 7,000 Fully breathable underlays The British Standard mainly distinguishes between two types of underlay: high resistance (HR) impermeable and low resistance (LR) vapour permeable. However, there are some manufacturers of low resistance underlays that claim their products are fully breathable, negating the requirement for ventilation as set out in the British Standard. There are a number of factors to consider before using any type of low resistance underlay, including: 1. How well-sealed the ceiling is 2. Whether a close-fitting roof covering is being used 3. Obstructions in the roof space In all circumstances, Marley Eternit recommend the use of additional ventilation when using any type of low resistance underlay. This can be achieved through the use of ventilated eaves and ventilated ridge systems. Close fitting coverings When specifying a close fitting covering which is relatively airtight (such as fibre cement slates), there is a risk of interstitial condensation forming on the underside of the underlay and the external covering. To avoid this risk, the batten space should be ventilated in accordance with BS 5250:2011 using counterbattens. 10,000 Normal ceiling 10,000 For sarking applications: Roof spans under N 10m (pitches under 35 ) 10,000 Normal ceiling Roof spans over 10m (or pitches over 35 ) 5,000 Normal ceiling 10,000 For sarking applications: Roof spans over 10m (or pitches over 35 ) Cold roof ventilation requirements 39 1

40 Warm roof ventilation requirements Key to illustrations Low Resistance underlay High Resistance underlay Warm pitched roof with HR underlay In roofs with an HR underlay, whatever form of external covering or ceiling is provided, there is a risk of interstitial condensation forming on the underside of the HR underlay. To avoid that risk, an AVCL (air vapour control layer) should be provided on the warm side of the insulation and ventilated voids should be formed between the underside of the underlay and the insulation. Each void should be at least 25mm deep and vented at both high and low level. Roofs with an AVCL Bituminous felts and vapour impermeable underlays (high resistance) The ventilation requirements for cold roofs with vapour impermeable underlays and 'well-sealed ceilings' are the same as those without. Installing a 'well-sealed ceiling' will make the roof more energy efficient because airtightness will have prevented heat loss through convection. Heat loss due to low speed air currents over the cold side of the insulation (caused by ventilation) is negligible. 25,000 50mm 5,000 Cold HR underlay 5,000 Cold 25,000 Warm pitched roof with LR underlay In warm pitched roofs with LR underlay, an AVCL should be provided at the ceiling line. If the external covering is sufficiently permeable, it will allow vapour to be released and no ventilation of the batten space is recommended. If it is not practicable to provide an AVCL, there might be some risk of interstitial condensation forming on the underside of the underlay. To avoid the risk, ventilated voids should be provided. Traditional underlay and AVCL (10-75 pitches) Vapour permeable underlays (low resistance) Where an AVCL has been installed, the harmful effects caused by condensation can be controlled by the use of a vapour permeable underlay without ventilation. The vapour permeable underlay may be laid fully supported on the insulation or draped unsupported. An AVCL is essential on the warm side of the insulation. If there is any doubt about the ability to provide and maintain an effectively sealed AVCL, then ventilation 5 should be provided as if the underlay were impermeable. LR underlay V LR underlay with AVCL 40 Warm roof ventilation requirements

41 Roofs with a close-fitting roof covering For warm roofs with a close-fitting roof covering, ventilation will be required either above or below the underlay, dependent on the underlay type. 25,000 25,000 50mm 50mm 5,000 Cold 5,000 Cold LR underlay HR underlay 5,000 Cold Ventilation void above underlay 5,000 Cold 25,000 5,000 25,000 25,000 Fully breathable underlays The British Standard mainly distinguishes between two types of underlay: high resistance (HR) impermeable and low resistance (LR) vapour permeable. However, there are some manufacturers of low resistance underlays that claim their products are fully breathable, negating the requirement for ventilation as set out in the British Standard. There are a number of factors to consider before using any type of low resistance underlay, including: 1. How well-sealed the ceiling is 2. Whether a close-fitting roof covering is being used 3. Obstructions in the roof space In all circumstances, Marley Eternit recommend the use of additional ventilation when using any type of low resistance underlay. This can be achieved through the use of ventilated eaves and ventilated ridge systems. Close fitting coverings When specifying a close fitting covering which is relatively airtight (such as fibre cement slates), there is a risk of interstitial condensation forming on the underside of the underlay and the external covering. To avoid this risk, the batten space should be ventilated in accordance with BS 5250:2011 using counterbattens. Ventilation void below underlay 5 V Warm roof ventilation requirements 41

42 Technical toolkit Tools and assets that make design and specification as straightforward as possible > NBS A tool to produce instant NBS clauses that meet the recommendations of British Standards and s of Practice: marleyeternit.co.uk/specrite > Dry fix selector Easy-to-use and comprehensive system finder delivering results from choice of pitch, material type or specific tile type: marleyeternit.co.uk/roofing > CAD details Access to over 2,000 CAD drawings illustrating how specific tile and slate details can be formed: marleyeternit.co.uk/cad > Tilefix Tool to create fixing specifications based on the geographical location and building dimensions of specific roofing projects: marleyeternit.co.uk/tilefix > CPDs A range of Continuous Professional Development roofing seminars accredited by the RIBA CPD Certification Service. For more information or to make a booking: marleyeternit.co.uk/cpd > Samples Samples of all fibre cement slates, clay and concrete tiles are available at: marleyeternit.co.uk/samples > BIM BIM Space is a set of free to download Building Information Modelling (BIM) objects that provide a standard range of build ups for our fibre cement roof slates, clay plain tiles and facades (EQUITONE and Cedral): marleyeternit.co.uk/bim > Fixing instructions & literature Comprehensive sitework, fixing and installation literature and videos: marleyeternit.co.uk/resources All current product and technical literature can be downloaded: marleyeternit.co.uk/downloads 42 Services

43 Services Getting our knowledge to you and your project smoothly and efficiently > Technical Advisory Service Specifiers require prompt, knowledgeable and detailed responses to a vast range of enquiries covering everything from the embodied energy of a typical roof tile, to the different ventilation options available. > Customer services Marley Eternit is committed to providing outstanding customer care and is staffed by experienced personnel: Tel info@marleyeternit.co.uk To find your nearest stockist, please visit: marleyeternit.co.uk/resources Our Technical Advisory Service is staffed by a qualified team with specialist knowledge not only of all Marley Eternit products, but also crucially, how those systems integrate with other roofing components and comply with Building Regulations, Health and Safety, environmental and other critical roofing criteria. Tel info@marleyeternit.co.uk Sustainability and standards Credits, credentials and clarity of information > BES 6001 Demonstrating our commitment to sustainable building, all our roofing products are certified under the BES 6001 standard for responsible sourcing and therefore contribute to extra credits under BREEAM and The for Sustainable Homes. > Embodied carbon Embodied carbon figures are available at product level for our entire roofing range. This absolute clarity of environmental information allows our customers to make informed choices. > BREEAM and the for Sustainable Homes Credits gained from specifying our A-rated products, combined with additional credits from BES 6001 make our products more beneficial to the specifier. > Quality standard All Marley Eternit s factories in the UK are ISO 9001, and ISO OHSAS accredited. They achieve the highest standards in quality, health and safety and the environment. > CE Marking All of our products covered by an EN Standard carry an appropriate CE Mark. This means that our products meet the required safety standards and have a guaranteed level of quality. This publication is based on the latest data available at the time of printing. Due to product changes, improvements and other factors, the Company reserves the right to change or withdraw information contained herein without prior notice. For specific applications users should refer to the Technical Advisory Service and relevant Standards and s of Practice for guidance. The photography shown in the document should not necessarily be taken as recommendations of good practice. Services 43

44 Call Or visit Marley Eternit Lichfield Road Branston Burton upon Trent DE14 3HD