Timber Flat Roof Construction Details Uk
Timber flat roof construction usually consists of structural joists topped with a decking of plywood or a similar sheet material.
Timber flat roof construction details uk. The pitch is governed by the roof covering and the required rate of rainwater discharge. Roof ridges and ridge tiles roof hips and hip tiles roof valleys roof verges and lead flashings. Others would treat even steeper pitches as flat roofs. There is also the scope to incorporate a green roof onto the flat structure.
Flat roof options help to free up internal space and are often cheaper that pitched roof options as they require fewer materials to cover the same roof span. Part 3 pitched roof detail. While many will contact a professional installation company to complete the job there are others who will feel confident enough in their own ability to install a flat roof onto the. The construction of the flat roof is similar to that of the timber upper floor.
Wherever possible joists should span the shortest distance of the roof plan. Joists are placed on edge spaced at 400 600mm centres supported by external and internal load bearing walls. It must provide adequate protection against the elements keeping the buildings structure and interior dry. There are two basic components of a timber roof.
The basic construction of a flat roof starts with roofing timber that is laid across two upright items usually two walls. For homebuilders a timber frame for a flat roof is usually the cheapest option and the easiest to build. Covers pitched roof detail. What pitch is a flat roof.
As with the construction of any type of roofing system it s crucial to understand the correct process and essential criteria involved in flat roofing construction. Flat roofs are exceedingly popular with those looking to create a cool modern home. 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. Having a manual for warm flat roof construction with details and a summary of rules to follow helps.
When building a flat roof it is vital that a degree of falls is built into the construction to ensure rainwater run off. Part 4 flat roof construction. A flat roof must be strong durable and stable throughout its lifetime. Covers pitched roof materials basic pitched roof designs cold and warm pitched roofs and pitched roof construction.
The supporting structure and the covering. For additional stability you can also use steel joists that are built into one or both of the walls. A roof is defined in bs 6229 as a flat roof if it has a pitch of 10 degrees or less. But this type of roof is seldom as attractive as the pitched form as it can result in a blocky stunted appearance.
The steels or rsj s rolled steel joists are often built into one or both walls to give added stability to the roof structure. Trada and approved document part a give guidance on sizes of joists for flat roofs relating to spans and loading.