Flat Timber Roof Structure

The flat roof is an architectural device that is loved by designers for its ability to create simplistic linear forms.

Flat timber roof structure.

On a basic level flat roof construction comes in the form of roofing timbers or joists as they are more commonly known or steels that are laid across two uprights walls in most cases. A cavity closer should be provided to the top of the walls to prevent fire spread and to stop damp air entering the roof space. For additional stability you can also use steel joists that are built into one or both of the walls. The construction of the flat roof is similar to that of the timber upper floor.

This will give additional stability to the roof structure. In most cases the roof can be erected in a day. Joists are placed on edge spaced at 400 600mm centres supported by external and internal load bearing walls. Flat roofs can be used to create box shapes cantilevered into daring overhangs or can be planted to create usable vegetated gardens.

Where a new flat roof abuts an existing external wall the joists can be hung on metal joist hangers which are fixed to a horizontal timber plate wall bolted to the wall. The steels or rsj s rolled steel joists are often built into one or both walls to give added stability to the roof structure. This house s roof construction used prefabricated trusses from turner timber with dormer windows factored into the design on the front elevation image credit. Load bearing or primary structure usually constructed in timber in a residential construction.