Minimum Gradient For Tiled Roof

What is the minimum slope for a clay or concrete tile roof.

Minimum gradient for tiled roof.

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 slope for asphalt shingles. Sunday july 1 2018 the international residential code irc specifies a minimum 4 12 pitch 4 inches of vertical rise for every 12 inches of horizontal run for a clay or concrete tile roof except that a pitch as low as 2 1 2 12 is allowed when two layers of underlayment are applied. Ratios from that minimum up to 4 12 which are considered low pitch require double underlayment.

Lapped nonsoldered seam metal roofs without applied lap sealant must have a minimum roof slope of 3 12 25 slope. Concrete is long lasting with a minimum lifespan of 50 years depending on climate. The requirements for an asphalt shingles roof are contained in the international building code. The following table provides the minimum required allowable roof slope for each type of roofing material mentioned in the code.

According to this code the minimum slope for asphalt shingles is 17 degrees or two vertical units to twelve units in the horizontal. Lapped nonsoldered seam metal roofs with applied lap sealant must have a minimum roof slope of 1 2 12 4 slope. The irc recommends a minimum pitch of 2 5 12 for these materials. Clay tiles are colorfast which means their tints improve rather than fade over time.

The minimum roof slope allowed by code for any type of roof is in 12 applicable only to coal tar pitch roof systems.