The recommendations shown above are based on a maximum height to eave of 12m and a maximum rafter length of 9m in moderate exposure and 6m in severe exposure.
Minimum pitch for blue slate roof.
Conventional low pitch slate roofs are recommended down to a minimum of 20 in areas of sheltered or moderate exposure providing a 500x300mm slate is used and a headlap of 115mm.
Minimum pitch for slate roof when considering the minimum pitch for a slated roof it is necessary to establish the exposure of the site the length of rafter and the height of the building.
But since there is still a wide variety of slate roofing systems there are occasions when the minimum pitch can go down to as low as 15 0 depending on the uniqueness of the roof.
Guidance on these components can be found in british standard bs 5534 2014 the code of practice for slating and tiling.
Type of slate being used.
Size of the lap.
The slope of a roof is often referred to as the roof s pitch.
Higher exposure or different sized slates necessitated a greater roof pitch of 22 5 or more.
Size of the slate.
Generally a slate roof is not installed on a pitch less than 4 12.
Minimum roof pitch for shingles.
Slate and slate type shingles require a minimum roof pitch of 4 12 or greater.
Wood shingles require a minimum roof pitch of 3 12 or greater.
Pitch of the roof.
What are the minimum pitches for clay or concrete tiles.
It is agreed that the roof pitch should be a minimum of 20 degrees preferably a bit more.
Our melodie interlocking clay pantile can be used in roof pitches as low as a 12 5 our wessex and mendip concrete roof tiles can be used down to a minimum 15 pitch.
Minimum recommended headlaps roofing the recommendations for minimum pitches and laps for slate tiles apply to normal situations.
You consider some alternative solutions.
Built up roofs require a minimum roof pitch of 1 4 12 or greater.
Wood shakes require a minimum roof pitch of 3 12 or greater.
Although bs 5534 recommends a minimum pitch of 20 ssq has developed a successful slate roofing system that allows the roof s pitch to be.
Mineral surfaced roll roofing requires a minimum roof pitch of 1 12 or greater.
There are some manufacturers that can go slightly lower such as the siga 56m natural slate which can go down to 20 in some instances if used with slate hook systems.
And our brand new mendip 12 5 can be used at an even lower pitch of 12 5 restrictions on rafter length may apply.
A couple of likely slate suppliers are consulted and they confirm that they are happy to supply 600x300mm slates for a minimum roof pitch of 20 degrees assuming a minimum lap of 125mm.
As per the nrca roofing and waterproofing manual fifth edition they recommend that roof deck slopes intended for the application of steep slope materials at 4 12 18 degrees or greater page 405.
