Timber Cold Flat Roof Construction

In the warm flat roof construction there is insulation packed into every possible space where air can flow.

Timber cold flat roof construction.

So any timber joists that are used need to be strong enough to support this weight. Old asbestos roofs are often replaced with flat roofs. There must be an adequate void minimum 50mm between the deck and the insulation traditionally mineral wool to allow free movement of air and to prevent moisture vapour being transmitted from the building outwards where it could condensate in the roof. Refurbishing an existing timber joisted flat roof which has no insulation.

A cold flat roof is one where the insulation is between or between and below the roof joists. As you may imagine there is a fair amount of weight involved here in terms of boards felt etc. Sizes of joists needed for flat roof construction. This ventilation is necessary to prevent condensation from forming below the roof deck which can.

This is used for refurbishment e g. Hopefully this video will help explain the difference between cold flat roof construction and warm flat roof construction this videos show detailed drawings. In a cold roof construction the sarnafil membrane is installed directly to the structural decking usually timber with firrings to fall.