Roof Pitch Multiplier Table

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.

Roof pitch multiplier table. 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. Roof pitch multiplier table.

This table provides the hip and valley factor for common roof pitches as well as the underlying equation for the factor. How to find your what roof pitch category. Determine how many square feet of roof area a building has by measuring from the ground. 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 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. With pitch under 3 you can easily walk on the roof to get the exact measurements as that is usually a flat roof. 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. The formula for the roof pitch multiplier comes from the famous pythagorean theorem.