EWI to slate roof verge with existing overhang [Version ID #114]

Author details

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Detail summary

Detail for EWI up to an existing overhanging verge with sufficient overhang to take depth of EWI with a new timber fascia board over at junction with roof. Mastic seal at all edges, existing membrane below eaves to be re-dressed over insulation.

Technical description

Section Detail. EWI to Verge, existing overhanging. 200mm depth woodfibre insulation or less. Existing roof and membranes to remain. No change/alteration to existing excluding addition of new fascia board.

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

  • External Wall Insulation (Woodfibre) System With Rendered Finish

    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


  1. Admin - 2015-04-29 14:44:46

    DWG file uploaded. PArts list amendments.

  2. Admin - 2015-03-27 16:57:56

    Preview image and .pdf file updated.

  3. Admin - 2015-03-24 17:34:09

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

  4. Admin - 2015-03-24 17:32:28

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

  5. Admin - 2015-03-13 15:31:21

    Technical description updated. Parts list updated.

  6. Admin - 2015-03-06 12:53:49

    Parts list updated.

  7. Admin - 2015-03-06 12:29:11 [Displayed version]

    Version 1

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