Timber Flat Roof Construction Details Uk

The definition of a flat roof according to bs 6229 is having a pitch less than 10 o to the horizontal however some in the industry would consider up to 15 o as their definition of a flat roof.

Timber flat roof construction details uk.

When building a flat roof it is vital that a degree of falls is built into the construction to ensure rainwater run off. Modern timber roofs are mostly framed with pairs of common rafters or prefabricated wooden trusses fastened together with truss connector plates timber framed and historic buildings may be framed with principal rafters or timber roof trusses roofs are also designated as warm or cold roof depending on how they are designed and built with regard to thermal building insulation and ventilation. Roofs tend to be either pitched or flat and typically in residential construction timber is the most common material used. It must provide adequate protection against the elements keeping the buildings structure and interior dry.

Getting the balance right here is crucial as too much weight will inevitably lead to an unstable roofing structure. A roof is defined in bs 6229 as a flat roof if it has a pitch of 10 degrees or less. The pitch is governed by the roof covering and the required rate of rainwater discharge. Wherever possible joists should span the shortest distance of the roof plan.

Part 4 flat roof construction. Others would treat even steeper pitches as flat roofs. Covers pitched roof materials basic pitched roof designs cold and warm pitched roofs and pitched roof construction. Covers pitched roof detail.

The building regulations in the uk provide guidance on roof design. The basic construction of a flat roof starts with roofing timber that is laid across two upright items usually two walls. For additional stability you can also use steel joists that are built into one or both of the walls. Flat roofing under construction plywood decking is then used to cover the joists with the width in between also determined by the weight being placed upon them.

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. Part 2 pitched roof construction. Roof ridges and ridge tiles roof hips and hip tiles roof valleys roof verges and lead flashings. Part 3 pitched roof detail.

The supporting structure and the covering. A flat roof must be strong durable and stable throughout its lifetime. There are two basic components of a timber roof. The roof is a key element of the building structure providing protection from the elements and has a vital role in reducing heat loss from the building.

Timber flat roofs timber flat roof construction usually consists of structural joists topped with a decking of plywood or a similar sheet material. For homebuilders a timber frame for a flat roof is usually the cheapest option and the easiest to build. But this type of roof is seldom as attractive as the pitched form as it can result in a blocky stunted appearance.