Rise Over Run Roof

The same pitch is also sometimes written as 4 12 4 in 12 or 4 over 12.

Rise over run roof.

That s the same as a 14 degree slope or a 25 slope. Why is the roof slope 25. A 3 in 12 roof rises 3 for every 12 of run. 3 of rise per 12 of run is the same as 1 of rise per 4 of run or 1 4 25.

The run is the distance from the outside of the wall to the inside of the ridge. On a 38 degree sloping roof angle t each individual vertical rise of 9 4 y 1 would have a horizontal run x 1 of 12 inches. Total roof rise or change in elevation for a 38 degree sloping roof angle t with one giant rise or step of 7 8 feet to the center of the attic y 2 would have total a run x 2 of 10 feet. The horizontal change in distance or the horizontal distance covered by an un supported rafter or truss.

In roof pitch calculator pitch value can be obtained by dividing n by 12 and divide s by the answer. Pitch is written assuming a run of a foot or 12 inches so the ratio describes how much the roof rises for every foot of its run. Last updated july 10 2020 the following table shows the roof pitch rise in run equivalents for all roof slopes in degrees from 1 to 72. Here is an online rise and run calculator which helps to calculate pitch slope and angle with the help of rise and run values.

Simply locate a roof rafter board place the end of the level against the bottom edge and measure from the 12 inch mark vertically to the bottom edge of the rafter. For example if you measure 4 inches the pitch of your roof is 4 12. This will give you the rise over run or pitch.