You can also divide the rise over run multiply by 100 and get a percentage.
Pitched roof slope angle.
You can assess this in two ways either as the roof pitch angles which the rafters make with the horizontal or the proportion between the run and the rise of the roof.
This means if a roof rises 4 in the length of 12 your roof pitch would be 4 12 or 18 43 degrees.
Thus a 4 12 pitch would be a 33 slope.
Roof pitch and corresponding angles.
Angle the angle of a roof is the same as the roof s slope except instead of being represented as x 12 it is represented in degrees.
In the roofing trade the go to term is pitch and it is expressed in terms of 12 inches so the pitch of a roof is determined by how many inches the slope rises for every 12 inches it runs horizontally.
Pitch angle incline slope they all can be used to refer to the steepness of a roof.
Roof pitch refers to the slope which the rafter creates.
A ratio is the most common way of expressing roof pitch or roof slope but degrees are also possible.
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.
This is useful because sometime you may need to cut a bevel with your circular saw that is not calibrated using roof pitch style this setting on circular saws is calibrated in degrees.