Slate and slate type shingles require a minimum roof pitch of 4 12 or greater.
Minimum pitch for eternit slate roof.
Please contact our technical advisory service.
The minimum roof slope allowed by code for any type of roof is in 12 applicable only to coal tar pitch roof systems.
With regards to the pitch the building standard code bs 5534 recommends a minimum pitch of 20 0 for slate roofs.
Higher exposure or different sized slates necessitated a greater roof pitch of 22 5 or more.
15 17 5 4m max.
Wood shingles require a minimum roof pitch of 3 12 or greater.
6m rafter length severe exposure.
17 5 20 6m max.
17 5 150mm lap max 9m rafter length the minimum recommended pitch and lap maybe influenced by special circumstances.
Wood shakes require a minimum roof pitch of 3 12 or greater.
Minimum pitch minimum pitch 100mm lap.
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.
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.
Mineral surfaced roll roofing requires a minimum roof pitch of 1 12 or greater.
15 150mm lap max.
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.
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.
Built up roofs require a minimum roof pitch of 1 4 12 or greater.
Severe exposure 22 5 low pitch application minimum pitch 110mm lap.
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.
The following table provides the minimum required allowable roof slope for each type of roofing material mentioned in the code.
35 17 5 17 5 smooth 22 5 smooth 15 smooth 22 5 smooth 30 22 5 15 25 smooth 22 5.
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.
