EWI to pitched roof, extended verge (existing roof support) [Version ID #112]

Author details

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Detail summary

Detail of EWI to the underside of a pitched slate roof with an extended verge. Where a pitched roof runs to the edge of an existing wall to be insulated, roof extended over new insulation. Timber ladder frame to support.

Technical description

Section detail. EWI verge detail, with extended slates, Slate roof.

Plan Detail. EWI carrying round brickwork step. Single-brick or equivalent step size. Woodfibre insulation system.

Care should be taken to ensure air-tightness. Seal all service penetrations. Lap and tape all membranes.

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: 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

  • External Wall Insulation (Woodfibre) System With Rendered Finish

    Composite woodfibre board. 100mm UdiTherm SK back board, 100mm 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.

  • Breather Membrane/ Roof-underlay

    Installation: Sealed to insulation to eaves and dressed to drainage point at the end of each run of guttering to allow water to exit construction.

    Green Building Store / Reference: Solitex UM


  1. Admin - 2015-04-29 14:23:16

    Title amendment. Technical description amended to remove notes on soil pipes and existing gas meters. DWG file uploaded.

  2. Admin - 2015-03-27 16:56:42

    Preview image and .pdf file updated.

  3. Admin - 2015-03-24 17:32:26

    General formatting. Technical description expanded with additional clauses and approved document links. Parts list updated with suppliers links.

  4. Admin - 2015-03-13 15:27:02

    Parts list updated. technical description expanded with BS EN detail and approved docs.

  5. Admin - 2015-03-06 12:25:55

    Technical description updated

  6. Admin - 2015-03-05 15:28:36 [Displayed version]

    Title update

  7. Admin - 2015-03-05 15:27:58

    First version

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