Flat Roof Pitch Requirements

The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles.

Flat roof pitch requirements.

It was fashionable for modern style homes built in the 1960s to have little pitch just a barely negligible slope to help drain water. Low pitched roofs are generally difficult to maintain and you need special materials to prevent leaks. They are common on extensions garages and commercial buildings. Steeper roof pitches are better at shedding rain and snow and are used more frequently in wetter colder areas 2.

Degrees to pitch rise in run table. As opposed to old built up. Think of a classic addams family haunted house with its soaring peaks and you have a. This pitch might be as low as 1 12.

Roofs on victorian era houses were often sharply angled with a steep pitch. Roof pitch multiplier table. Wood shingles require a minimum roof pitch of 3 12 or greater. This is the basis for calculating the angle which is approximately a 1 19 degree slope.

However you can only use this pitch with built up roofing or specialized synthetic roofing. The chief reason for having a roof pitch is to redirect water and snow away from the roof and avoid any percolation that might result from stagnation of water on the roof. Flat roofs which aren t perfectly flat require a small slope to allow for water runoff. Slate and slate type shingles require a minimum roof pitch of 4 12 or greater.

These roofs have a pitch less than 4 12. The minimum pitch for a roof is 1 4 12 which translates to 1 4 inch rise to 12 inches of run. According to the international building code the typical built up flat roof that uses tar or asphalt goes by the guideline that for every foot 12 inches of a flat roof a minimum of inch must step up or down. However pitched roofs are still used as roof trusses are a very economic way of spanning between side walls.

Asphalt shingles continue to be the most widely installed roof covering option in north america. They provide excellent weather resistance great value and now more than ever a tremendous range of beautiful designs and color blends. Flat roofs are an often lower cost and easier to install alternative to traditional pitched roofs. Roof slope equivalents as rise.

Pitched roofs are attractive and also. Generally such roofs have a pitch ranging from 1 2 12 to 2 12. Mineral surfaced roll roofing requires a minimum roof pitch of 1 12 or greater. Wood shakes require a minimum roof pitch of 3 12 or greater.

Run in degrees and as percentage the minimum roof slope allowed by code for any type of roof is in 12 applicable only to coal tar pitch roof systems. What is a flat roof. If you re thinking of installing a flat roof it s important to make sure you are up to date with all the rules and regulations before you begin with a new flat roof construction. The minimum roof pitch is also subject to the standards set forth by the various building codes used in the respective regions.

Visually this roof appears flat.