Roof Pitch Multiplier Table

How to find your what roof pitch category.

Roof pitch multiplier table.

A roof pitch multiplier also called a roof pitch factor is a number that is multiplied by the area covered by a sloped roof to produce the area of the actual surface of the roof. The roof pitch multiplier table is very helpful in giving correct and reliable roof measurements and uses pythagorean theory. Now solving for c in the equation above gives. For roof slopes expressed as x in 12 rise in run the roof pitch multiplier is determined by finding the square root of rise run 1.

If you know the pitch of a roof you can use the numbers in the following pitch table to do the following. We excluded roof multipliers for pitch below 3 and above 12 for the following reasons. This table provides the hip and valley factor for common roof pitches as well as the underlying equation for the factor. The formula for the roof pitch multiplier comes from the famous pythagorean theorem.

This roof pitch table displays a multiplier for adding for different roof pitches. Where a is the rise of the roof b is the run of the roof and c is the rafter hypotenuse of the triangle with side lengths a and b. Roof pitch multiplier table. The hip and valley factor is a number that is multiplied by the actual run horizontal distance of a common rafter to determine the length of a hip or valley rafter.