Formula To Find The Slope Of A Roof

The picture below shows the pitch of a 7 12 roof slope meaning that for 12 of horizontal measurement roof run the vertical measurement roof rise is 7.

Formula to find the slope of a roof. Outside of the u s a degree angle is typically used. Slope tan degrees. In the imperial unit of measurements the slope is expressed with the rise and run. Roof slope is also called as roof pitch.

The run always remains constant at 12 inches. Image 1 12 to 12 12 roof pitch 7 12 pitch. In civil engineering the slope is the numerical measure of the steepness of a roof. A flat roof has a slope of 2 in 12 or less.

The slope of your roof is the ratio of vertical distance rise to horizontal distance run. For instance a 7 12 roof pitch means that the roof rises 7 inches for every 12 horizontal inches. It is often compared to slope but is not exactly the same. You can use the following equations to find the length of the rafter and the slope.

Then multiply the slope by 12 to get the rise. You can also calculate roof pitch even without using a roof slope calculator. Just write down the measurements you found. Generally roof pitch is calculated from the same formula that describes a right triangle.

As a sanity check we confirm that the tangent of 45 degrees is 1 or that two opposed 45 degree or 12 in 12 slope roof surfaces will form a 90 degree angle where they meet at the ridge and will form 45 degree angles where they meet the wall top plate or with respect to any horizontal line in the building. If you know the angle of the roof in degrees you can find the roof pitch by converting the angle in degrees to a slope then finding the rise by multiplying the slope by 12. This is very useful information for many purposes especially for roof framing the slope sometimes called pitch is calibrated on speed squares. Here are the equations you may use to solve for the length of the slope and the rafter.

That is the roof s rise. Roof pitch degree table. Rise run pitch where pitch is expressed in percent. Use the following formula which also describes a right triangle.

Rafter rise run this formula is from the pythagorean theorem. Roof pitch calculator results explained slope the slope of a roof is represented as x 12 where x is the number of inches in rise for every 12 inches of run. There are two main categories of roofing. There s no need to simplify them.

Conventional slope roof range between 4 in 12 and 8 in 12. A low slope roof is anywhere from 2 in 12 to 4 in 12. Tan 45o 1 00. Roof slope style.

How to calculate roof pitch. In the united states a run of 12 inches 1 foot is used and pitch is measured as the rise of the roof over 12 inches.