21 12 Roof Pitch

On blue prints architects engineers usually display the pitch of a roof in the format shown on the image where number 4 represents a rise and number 12 represents a length.

21 12 roof pitch. Click here to view our roof pitch diagram chart. The table below shows common roof pitches and the equivalent grade degrees and radians for each. Use the following formula which also describes a right triangle. A pitch over 9 12 is considered a steep slope roof between 2 12 and 4 12 is considered a low slope roof and less than 2 12 is considered a flat roof.

Divide the rise by the run the run is 12. They hava a pitch that can be as high as 21 12 175. 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 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. Generally roof pitch is calculated from the same formula that describes a right triangle.

High pitched roofs often need extra fasteners and their pitch can be as high as 21 12. This means if a roof rises 4 in the length of 12 your roof pitch would be 4 12 or 18 43 degrees. Active ventilation products.