A 4 12 pitch is around 18 5 degrees but not exactly.
Pitch roof slope angle.
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.
Rise run rise run slope.
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.
A ratio is the most common way of expressing roof pitch or roof slope but degrees are also possible.
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.
First convert the pitch to a slope.
The minimum roof pitch for shedding snow is around 30 or a 6 12 or 7 12 slope although this is not a definite as the material of your roof the direction of the snow and wind are some factors that can affect whether or not snow will slide as roofs of as little as 10 have been reported to shed snow.
Roof pitch is a term describing how steep or flat your roof slope is.
Roof pitch angle and slope factor charts.
Roof pitch refers to the slope which the rafter creates.
Often you express roof pitch as the ratio between the rise and the run in the form of x 12.
You can also divide the rise over run multiply by 100 and get a percentage.
Thus a 4 12 pitch would be a 33 slope.
The combination of two numbers are used to display or show the roof pitch.