The pitch is governed by the roof covering and the required rate of rainwater discharge.
Timber flat roof construction details uk.
What pitch is a flat roof.
Covers flat roof materials and flat.
The steels or rsj s rolled steel joists are often built into one or both walls to give added stability to the roof structure.
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.
A flat roof must be strong durable and stable throughout its lifetime.
But this type of roof is seldom as attractive as the pitched form as it can result in a blocky stunted appearance.
A roof is defined in bs 6229 as a flat roof if it has a pitch of 10 degrees or less.
It must provide adequate protection against the elements keeping the buildings structure and interior dry.
Joists are placed on edge spaced at 400 600mm centres supported by external and internal load bearing walls.
There are two basic components of a timber roof.
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.
The construction of the flat roof is similar to that of the timber upper floor.
The basic construction of a flat roof starts with roofing timber that is laid across two upright items usually two walls.
Part 4 flat roof construction.
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.
For additional stability you can also use steel joists that are built into one or both of the walls.
Covers pitched roof detail.
Roof ridges and ridge tiles roof hips and hip tiles roof valleys roof verges and lead flashings.
There is also the scope to incorporate a green roof onto the flat structure.
Wherever possible joists should span the shortest distance of the roof plan.
The supporting structure and the covering.
Flat roofs are exceedingly popular with those looking to create a cool modern home.
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.
Covers pitched roof materials basic pitched roof designs cold and warm pitched roofs and pitched roof construction.
Having a manual for warm flat roof construction with details and a summary of rules to follow helps.
Others would treat even steeper pitches as flat roofs.
Part 2 pitched roof construction.
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 usually consists of structural joists topped with a decking of plywood or a similar sheet material.
Trada and approved document part a give guidance on sizes of joists for flat roofs relating to spans and loading.
