Maximum Roof Pitch For Slate

The recommendations for minimum pitches and laps for slate tiles apply to normal situations.

Maximum roof pitch for slate.

Roof tiles and slates are very versatile products and can be used on a variety of roof pitches. 11 august 2015 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. In general the recommendations apply to rafter lengths of not more than 9m in driving rain exposures of less than 56l m2per spell and 6m in driving rain exposures greater than 56 l m2per spell. It is agreed that the roof pitch should be a minimum of 20 degrees preferably a bit more.

The result of your conversation is as follows. 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. Higher exposure or different sized slates necessitated a greater roof pitch of 22 5 or more. Slate pitch 8 12 20 12 3 headlap.

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. 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. 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. Tiles or slates can be used at pitches up to 90 degrees vertical provided a clip is available to securely clip the tail of the tile available for most tiles.

Formula to adjust pieces per square based on headlap requirements 1 square covers 100 square feet. Slate pitch greater than 20 12 2 headlap 20 rise per 12 run 59 04 angle of incline.