Calculate the roof pitch as the proportion of rise and run.
Roof rise in degrees.
Finally you can find the roof pitch in the form of x 12.
This measurement is best done on a bare roof because curled up roofing shingles will impair your measurement.
Recalculate this value into an angle.
Locate its tangent or tan and follow the left row for you to read its corresponding degree.
Roof pitch to degrees equivalents this drawing demonstrates how many degrees rise for each pitch of a typical roof.
Rafter rise run this formula is from the pythagorean theorem rise run pitch use this when you express the pitch in percent pitch tan angle use this when you express the angle of the roof pitch in degrees what is the standard pitch of a roof.
Roof pitch and corresponding angles.
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.
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.
Here are the equations you may use to solve for the length of the slope and 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.
The following table shows the roof pitch rise in run equivalents for all roof slopes in degrees from 1 to 72.
First find the slope by finding the tangent of the degrees eg.
Last updated july 10 2020.
8 12 pitch 33 75 degrees.
Roof slope definitions measurement methods.
Rafter rise run 1 5 6 2 25 36 38 25rafter 38 25 6 18 m.
Look at the column labeled pitch then look under degrees to get the corresponding amount of degrees.
Angle arctan pitch arctan 0 25 14.
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.
Identify the rise and run.
Determine its angle through taking a 12 inch level and.
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.
Slope tan degrees.
Roof slope expressed as rise.
Divide its rise by run in.
This means if a roof rises 4 in the length of 12 your roof pitch would be 4 12 or 18 43 degrees.
To see what the degree equivalents are for standard rise in run roof pitches see our page quick reference.
Then multiply the slope by 12 to get the rise.
We give the required roof slopes for different types of roofing materials and we illustrate several methods by which the slope or pitch of a roof is easily measured.
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.
