Roof insulation at increased depth rafters [Version ID #88]

Author details

Original Author:Admin Organisation:

Detail summary

Insulation detail where existing rafters are extended to allow greater depth of insulation. Use only where suitable vapour-permeable roofing membrane is present (check brand and sd value).

Technical description

Section detail. Roof insulation to existing room-in-roof with no existing sarking or vapour permeable membrane present.

Removal of existing ceiling and finishes (set aside for re-use), remove existing light fittings and set aside for re-use. Remove any existing timber mouldings. Check roofing membrane before installation of insulation.

Parts list

  • Increased depth to rafters

    C16 strength class, FSC certified timber to increase existing rafters to 250mm. Fixed to existing rafters at existing centres.

    Contractors choice.

  • Insulation Boards Or Batts Fitted Between Rafters

    Woodfibre batts, friction fitted between rafters. \ Thickness 250mm. Width to suit rafter spacing. \ Thermal conductivity: 0.40W/m2K. GWP 0.

    Unger \ www.unger-diffutherm.de \ Reference: UdiFLEX

  • Single layer plasterboard backings (nail fix) and plaster

    Vapour check plasterboard 12.5mm thickness tapered edge. Joints taped. \ With 2-3mm gypsum plaster coat over applied in single coat, smooth finish

    Contractors choice

Revisions

  1. Admin - 2015-04-30 10:55:29

    DWG uploaded. General formatting work to parts list.

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  2. Admin - 2015-03-30 11:40:44

    Preview image and detail pdf updated. Title amended to match drawing.

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  3. Admin - 2015-03-28 18:04:39

    Intelligent membrane amended in parts list.

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  4. Admin - 2015-03-19 13:28:25

    Version 2 -Title updated. Errors is introduction removed.

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  5. Admin - 2015-03-19 13:27:48

    Title updated. Errors is introduction removed.

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  6. Admin - 2015-03-18 10:36:36

    Version 2- Introduction expanded with additional information. Technical description expanded with BS codeas an approved doc links. Parts list codes and manufacturers links added.

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  7. Admin - 2015-03-04 14:26:13

    Version 2- preview image revised.

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  8. Admin - 2015-03-04 14:20:27 [Displayed version]

    First version

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