Slate Roof Minimum Slope

This means for every 12 horizontal units the roof must rise a minimum of 4 vertical units.

Slate roof minimum slope.

Express the slope of a metal roof by a ratio which indicates the pitch of the roof. You need to consider the slope requirements of each panel to determine this minimum slope. Minimum roof slope roof pitch r905 6 2 slate shingles can only be installed on roof slopes of 4 12 or greater 33 slope. The following table provides the minimum required allowable roof slope for each type of roofing material mentioned in the code.

Generally a slate roof is not installed on a pitch less than 4 12. 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. Minimum roof pitch for shingles. The general recommendation for the minimum pitch for natural slate is 25.

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. The profile is the shape taken by the sheets when you bend them to form panels. 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. The minimum slope of a roof depends on the roof s profile.

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. 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 minimum roof slope allowed by code for any type of roof is in 12 applicable only to coal tar pitch roof systems. 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 reduced to 17 5 generally and under some circumstances as low as 15 in areas considered to be unexposed.

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. The slope of a roof is often referred to as the roof s pitch. The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles.