Roof Pitch Multiplier Table

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 formula for the roof pitch multiplier comes from the famous pythagorean theorem. How to find your what roof pitch category. 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. The roof pitch multiplier table is very helpful in giving correct and reliable roof measurements and uses pythagorean theory.

Accurate roof calculations are achieved using this table and all you need to do is measure the roof width and length and then you are ready to do a roof pitch measurement. If you know the pitch of a roof you can use the numbers in the following pitch table to do the following. This table provides the hip and valley factor for common roof pitches as well as the underlying equation for the factor. This roof pitch table displays a multiplier for adding for different roof pitches.

Roof pitch multiplier table. With pitch under 3 you can easily walk on the roof to get the exact measurements as that is usually a flat roof. 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. We excluded roof multipliers for pitch below 3 and above 12 for the following reasons.