17 5 20 6m max.
Minimum pitch for eternit slate roof.
The following table provides the minimum required allowable roof slope for each type of roofing material mentioned in the code.
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.
6m rafter length severe exposure.
Traditionally a minimum roof pitch of 20 was recommended in bs 5534 but modern tiles and slates have now been designed for applications as low as 15.
Severe exposure 22 5 low pitch application minimum pitch 110mm lap.
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.
15 17 5 4m max.
35 17 5 17 5 smooth 22 5 smooth 15 smooth 22 5 smooth 30 22 5 15 25 smooth 22 5.
Please contact our technical advisory service.
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.
Slate and slate type shingles require a minimum roof pitch of 4 12 or greater.
It is uncommon to find a roof below 15 but for those very low pitch applications there are interlocking clay pantiles available suitable for use down to 12 5.
Mineral surfaced roll roofing requires a minimum roof pitch of 1 12 or greater.
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.
Built up roofs require a minimum roof pitch of 1 4 12 or greater.
With regards to the pitch the building standard code bs 5534 recommends a minimum pitch of 20 0 for slate roofs.
17 5 150mm lap max 9m rafter length the minimum recommended pitch and lap maybe influenced by special circumstances.
Higher exposure or different sized slates necessitated a greater roof pitch of 22 5 or more.
The minimum roof slope allowed by code for any type of roof is in 12 applicable only to coal tar pitch roof systems.
Formerly under the brand name of eternit we are the uk s most experienced company when it comes to fibre cement slates and are proud to have been putting roofs over heads for decades.
With more cement and fibres than any other cedral slates are the strongest slates in the market and tough enough to withstand the most volatile weather.
25 minimum pitch 110mm lap.
Wood shakes require a minimum roof pitch of 3 12 or greater.
14 8 slates m at 150mm headlap.
