There are two types of flat roof system and they differ according to whether the insulation is above or below the structural roof deck.
Timber flat roof design.
Having a manual for warm flat roof construction with details and a summary of rules to follow helps.
As you may imagine there is a fair amount of weight involved here in terms of boards felt etc.
Flat roofs are hard to replace.
For additional stability you can also use steel joists that are built into one or both of the walls.
Roofs tend to be either pitched or flat and typically in residential construction timber is the most common material used.
Some observers suggest it s harder to replace a flat roof than a traditional pitched shingle roof because of the labor required to remove its layers especially on older flat roofs.
The building regulations in the uk provide guidance on roof design.
This includes structural joists to hold up a roof deck usually of timber boarding a suitable membrane to reduce the risk of condensation and a layer of insulation to keep the warmth in.
Today flat roofs are used by architects for the same reasons that they became a cornerstone of modernist architecture.
But now flat roofs often are constructed with fewer layers because of improved waterproofing technology.
Sizes of joists needed for flat roof construction.
May 9 2017 explore bernice ohene s board flat roof construction on pinterest.
Flat roof with no permanent access and altitude not exceeding 100m 0 75 kn m udl 0 9 kn point load most areas exceeding 100m but not exceeding 200m excluding parts of scotland pennines north east england refer to bs 6399 3 1 kn m udl 0 9 kn point load.
You can find the building regulations here.
The basic construction of a flat roof starts with roofing timber that is laid across two upright items usually two walls.
This could mean flat roofs may not raise the same red flags they used to.
Old asbestos roofs are often replaced with flat roofs.
So any timber joists that are used need to be strong enough to support this weight.