Minimum Pitch For Slope Roof

The minimum pitch for a roof is 1 4 12 which translates to 1 4 inch rise to 12 inches of run.

Minimum pitch for slope roof. If a roof slope rises say 4 inches when measured 12 inches along the bottom of a horizontal roof truss the roof slope is said to be 4 12. 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 requirement is 2 12. However roof pitch is technically measured and defined differently.

Shingles of all types need to have a slope to function properly. The 2 12 number is rise over run or two units of vertical for every 12 units horizontal. The minimum pitch is typically 3 12 meaning the roof should rise 3 inches for every 12 inches of horizontal foot. What is the minimum pitch slope of an asphalt shingle roof.

With regards to the pitch the building standard code bs 5534 recommends a minimum pitch of 20 0 for slate roofs. The minimum roof slope allowed by code for any type of roof is in 12 applicable only to coal tar pitch roof systems. I e 4 inches of rise per 12 inches one foot of run. However you can only use this pitch with built up roofing or specialized synthetic roofing.

The standard of lower pitch actually ranges between 1 12 to 5 12. That works out to about nine degrees if that works better for you.