Here is an online rise and run calculator which helps to calculate pitch slope and angle with the help of rise and run values.
Rise over run roof.
Why is the roof slope 25.
In roof pitch calculator pitch value can be obtained by dividing n by 12 and divide s by the answer.
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.
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.
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.
The same pitch is also sometimes written as 4 12 4 in 12 or 4 over 12.
For example a roof that rises 4 inches for every 12 inches of run has a 4 12 pitch.
For example if you measure 4 inches the pitch of your roof is 4 12.
3 of rise per 12 of run is the same as 1 of rise per 4 of run or 1 4 25.
That s the same as a 14 degree slope or a 25 slope.
A 3 in 12 roof rises 3 for every 12 of run.
The run is the distance from the outside of the wall to the inside of the ridge.
The rise is the distance from the top of the roof to the bottom.
Other than the 45 roof slope which is 12 in 12 none of the standard roof pitches 5 in 12 6 in 12 etc are equal to a whole degree.
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.