Roof Math Formula

Length of rafter suppose a roof has a rise of 18 inches and a run of 15 feet.

Roof math formula.

Rafter rise run this formula is from the pythagorean theorem. In particular roofers have to use geometry to determine the length and the angle to which to cut the rafters. Carpenters prefer to use pitch in calculations instead of rise and run. To figure out your roof s area a simple geometry can be used.

Here are the equations you may use to solve for the length of the slope and the rafter. The key is to be as accurate as possible since falling short or an overage could mean thousands of dollars when planning your roofing budget. Formula this page offers you the rise and run formula to find the pitch slope angle of the roof of a building. You can also calculate roof pitch even without using a roof slope calculator.

Roofers have to use it when constructing a frame for a new roof or when repairing a frame. A roof pitch multiplier also known as a roof pitch factor is a number that when multiplied by the area covered by a sloped roof gives the actual area of the roof. They have to do this with a formula that takes into account the rise of the roof the vertical height and the run the horizontal length. Below there is a simple triangle and the math used to work out.

Use the following formula which also describes a right triangle. Roofing is measured in squares. Roof slope is also called as roof pitch. The maths behind this number is that it is the square root of rise run 2 1.

Slope measures the angle of change in elevation which can be obtained by dividing rise by run and multiply the result with 100. In civil engineering the slope is the numerical measure of the steepness of a roof.