A 12 12 pitch roof has a pitch angle of 45.
20 degree slope roof.
Divide the first part of the ratio by 12 to work out the pitch.
To do this simply convert the rise and run as a fraction to a decimal form eg.
This measurement is best done on a bare roof because curled up roofing shingles will impair your measurement.
Enter run the flat level length then click pitch angle or rise to select then enter other known dimension angle or pitch.
For a pitch expressed in inches per foot convert to a fraction.
This chart covers a wider range.
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.
Drag sliders to animate the results and diagram.
To find the angle of a roof in degrees convert the pitch to a slope then convert to degrees by finding the arc tangent of the slope.
Roof slopes are identified using the gradient method described above where the rise varies but the run is usually 12.
Roof pitch refers to the measurement of the slope of a roof and you express this as a ratio.
Rise run rise run slope.
Enter 2 44992 and reading the second output line we see this yields a 1 in 40 ratio and a 1 4321 degree angle.
Find the inverse tangent of the pitch to find the angle in degrees.
However if you to do the process using your own knowledge you can still convert pitch to degrees by dividing the rise and run and get its corresponding measurement.
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.
Traditionally a minimum roof pitch of 20 was recommended in bs 5534 but modern tiles and slates have now been designed for applications as low as 15.
The graph towards the top of the page shows a small range of angles from zero to 20 degrees.
It is uncommon to find a roof below 15 but for those very low pitch applications there are interlocking clay pantiles available suitable for use down to 12 5.
The following table shows the roof pitch rise in run equivalents for all roof slopes in degrees from 1 to 72.
To convert between american roofing ratios and pitch degrees follow these steps.
First convert the pitch to a slope.
Let s suppose we are entering a grade that was computed by rise over slope length.
What degree angle is a 12 12 pitch roof.
In some very steep roofs you may see the gradient inverted so that the run varies but the rise is held as 12.
With the use of this converter it will be easier for you to locate a 30 degree roof pitch 20 degree roof pitch 25 degree roof pitch or a 15 degree roof pitch.