Timber Flat Roof Detail

The basic construction of a flat roof starts with roofing timber that is laid across two upright items usually two walls.

Timber flat roof detail.

Contemporary designers frequently aim to produce the same clear and simplified forms that appeared at the beginning of the 20th century but are now free to use a wide range of new materials and construction techniques that reflect present day technology. Parapet detail joists perpendicular 3 13. Intermediate floor joist parallel 4 3. Flat roofs aren t actually flat but must slope to drain water.

Trada and approved document part a give guidance on sizes of joists for flat roofs relating to spans and loading. Joists are placed on edge spaced at 400 600mm centres supported by external and internal load bearing walls. The construction of the flat roof is similar to that of the timber upper floor. Today flat roofs are used by architects for the same reasons that they became a cornerstone of modernist architecture.

Having a manual for warm flat roof construction with details and a summary of rules to follow helps. 2 ply rigid plastic foam board vapour barrier separating membrane. Dormer in section 3 11. For additional stability you can also use steel joists that are built into one or both of the walls.

The abutment detail of a flat roof is vital in order to prevent moisture penetration. It dealt in detail with flat roof constructions and can be regarded as one of the first guidelines for such roofs fig. Similar to the abutment of a lean to roof lead flashing is chased into the external block allowing it to overlap the lead upstand coming from the tiles. Parapet detail joists parallel details in section 4.

Dormer in perspective view 3 12. 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. Timber flat roof carports timber flat roof construction timber flat roof construction details timber flat roof deck timber flat roof detail timber flat. Roof panels 3 8 1 roof panel connections 3 9.

The steels or rsj s rolled steel joists are often built into one or both walls to give added stability to the roof structure. Underneath the basics flat roofs are usually constructed with a ceiling nailed to joists which support a deck usually wood in residential construction a vapor barrier insulation and a roof board. Normally a slope of inch per foot is used. Flat roof joist and decking 3 10.