EWI to soffit eaves by room-in-roof [Version ID #229]
Detail summary
EWI designed to deal with potential cold bridge at eaves - where loft or roof insulation meets external wall insulation and there is a deep enough soffit for EWI to slot beneath. Installed from outside.
Technical description
Section detail. EWI to existing wall. Up to eaves soffit, with new phenolic foam insulation to join to EWI.
SUGGESTED INSTALLATION SEQUENCE:
Lift bottom three/four rows of slates/tiles and associated battens as required. Roll back any existing roofing membrane. Insert rigid insulation piece between the rafters, leaving a minimum of 25mm between the top face and top side of rafter. Notch rigid insulation over sole plate to ensure no gap between top of ceiling and underside of rigid insulation. Fill gaps between the outer face of the sole plate, the top of the brickwork and the inside face of the external wall insulation to minimise air gaps within construction. Dress rigid insulation board against the inside face of the eaves fascia board. Glue battens to upper surface of the cut slabs 100mm in from each edge. Fit over fascia eaves ventilator. Re-fix roofing membrane and tape to new membrane. Re-fix existing battens and slates/tiles.
REFERENCE SPECIFICATION:
Tiling work: Clay tiles to BS EN 1304/ concrete (non interlocking) to BS EN 490. All battens/counterbattens and ridge/hip fixing battens to be timber species to BS 5534, Clause 4.12.1. All fasteners to BS 1202 as appropriate to fastener type
Existing guttering to be replaced/reinstated to BS EN 607, and BS EN 1462, Kitemark certified, clauses 3–7 and National Annexes. Collection and distribution of rainwater: Complete, and without leakage or noise nuisance. Reference should be made to Approved Document H (drainage and waste disposal) and Document F (ventilation)
Care should be taken to ensure air-tightness. Seal all service penetrations through EWI and existing wall. Lap and tape all membranes around edges of EWI system.
All insulation to be continuous to avoid thermal bridging.
Preparation of external wall: Remove any existing loose material and prepare in accordance with manufacturer's requirements.
Any alterations to drainage and other fixtures, or work to prepare the substrate, to be agreed with contract administrator prior to work being undertaken. Prior to start on site inspect the form and condition of the structural substrate; institute repairs and/ or additional works necessary to make the substrate suitable to receive EWI system.
Parts list
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Insulation To Eaves (Flexible) [RF06a]
Woodfibre off-cuts from EWI/ IWI etc. \ Applied into any gaps between wall plate/ top of wall/ rigid insulation/ external wall insulation to ensure continuity of insulation and avoid air movement.
Unger \ www.unger-diffutherm.de \ Ref: Diffutherm
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Insulation to Eaves (rigid) [RF06a]
Phenolic Foam. \ Thermal conductivity: 0.023W/m2k. \ Thickness: 50mm nominal (to maintain 25mm minimum ventilation gap). \ Width: Cut to suit rafters. \ Length: 600mm minimum - to ensure overlap with loft/roof insulation and any wall insulation and avoid thermal bridge. \ Installation: Continuous with roof insulation, no gaps, to avoid cold bridging. Friction fit between rafters.
Contractor's choice
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Breather Membrane [RF06a]
Flexible damp proofing sheet. To Packaging and Industrial Films Association (PIFA) Standard 6/83A, or Agrément certified. Sealed to phenolic foam insulation and dressed to drainage point at the end of each run of guttering to allow water to exit construction. Accessories: Tyvek 2060B Tape.
DuPont Tyvek. \ http://www.dupont.co.uk/products-and-services/construction-materials/tyvek-building-envelope.html \ Ref: Tyvek Supro
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Over Fascia Eaves Ventilator [RF06a]
Ventilator strip to allow airflow under roof whilst preventing ingress of insects and small birds.
Hambleside Danelaw Ltd. \ www.hambleside-danelaw.co.uk \ Ref: HD12000U Universal Over Fascia Ventilator or equivalent
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Double/Single-sided air seal tape [DP09b/a]
Tape for junctions critical to air-tightness. 60mm (typical). \ Accessories: ORCON F sealant and TESCON PRIMER RP (for use on rough/old surfaces to assist adhesion)
Pro Clima \ http://www.greenbuildingstore.co.uk/page--pro-clima-airtightness-tapes-options.html \ TESCON VANA/ TESCON PROFIL (single sided) \ Contega L (double sided)
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EWI (Woodfibre), rendered finish [EW01]
For use on solid and hard to treat cavity walls. Composite woodfibre board. UdiTherm SK back board, Diffutherm NF (T&G, renderable) top board. \ Fixed mechanically to substrate in accordance with manufacturers recommendations. \ Base Coat - levelling on substrate: 90% contact required around edge of boards between board and substrate to prevent thermal bypass. If substrate is very uneven, use base-coat material around edge of board to achieve contact. \ Thermal conductivity: 0.045W/m2K. GWP 0.
Unger \ www.unger-diffutherm.de \ Reference: UdiFRONT. \ Render: UDI Perl
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Softwood battens (for replacing existing slating) [RF06a]
As existing size. Fully factory Pre-graded. \ All timber to be FSC certified \ Preservative treatment required. \ Fastening: glued.
Contractors choice.
Revisions
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Admin - 2015-04-29 09:37:37
DWG uploaded. Back To Earth added to contacts list for EW01.
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Admin - 2015-04-22 14:26:02
Pdf file updated to match parts list codes
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Admin - 2015-03-27 16:18:26
Preview image and .pdf file updated.
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Admin - 2015-03-27 11:30:53
Codes updated, concurrent with drawing.
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Admin - 2015-03-23 16:02:27
Parts list formatting
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Admin - 2015-03-23 13:06:44
General formatting. Intro updated and expanded. Technical description updated with Approved doc links, and revised installation sequence. Parts list updated with codes and Links to suppliers/manufacturers.
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Admin - 2015-03-13 18:06:59 [Displayed version]
Technical description updated. Suggested installation sequence added. Parts list updated.
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Admin - 2015-03-12 13:39:06
Version 4. Title and intro summary updated. Technical description updated and expanded. BS and Approved doc information added. Parts list updated. Preview image and pdf file updated with revised linetype colours /line-weights
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Admin - 2015-03-03 12:19:17
Parts list updated
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Admin - 2015-02-27 12:17:32
Version 2 - .dwg file updated
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Admin - 2015-02-26 14:51:53
First Version
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For those who have seen the Earth from space, and for the hundreds and perhaps thousands more who will, the experience most certainly changes your perspective. The things that we share in our world are far more valuable than those which divide us.
For those who have seen the Earth from space, and for the hundreds and perhaps thousands more who will, the experience most certainly changes your perspective. The things that we share in our world are far more valuable than those which divide us.
- Ease of understanding detail: Easy
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For those who have seen the Earth from space, and for the hundreds and perhaps thousands more who will, the experience most certainly changes your perspective. The things that we share in our world are far more valuable than those which divide us.
For those who have seen the Earth from space, and for the hundreds and perhaps thousands more who will, the experience most certainly changes your perspective. The things that we share in our world are far more valuable than those which divide us.
- Ease of understanding detail: Easy
- Ease of sourcing materials: Easy
- Ease of sourcing skills: Easy
- Ease of implementation: Easy
- Overall cost: Low cost
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User name
For those who have seen the Earth from space, and for the hundreds and perhaps thousands more who will, the experience most certainly changes your perspective. The things that we share in our world are far more valuable than those which divide us.
For those who have seen the Earth from space, and for the hundreds and perhaps thousands more who will, the experience most certainly changes your perspective. The things that we share in our world are far more valuable than those which divide us.
- Ease of understanding detail: Easy
- Ease of sourcing materials: Easy
- Ease of sourcing skills: Easy
- Ease of implementation: Easy
- Overall cost: Low cost
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For those who have seen the Earth from space, and for the hundreds and perhaps thousands more who will, the experience most certainly changes your perspective. The things that we share in our world are far more valuable than those which divide us.
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