To determine the y height measure from the bird s mouth up the calculated slope x in 12 to the top of the rafter.
Peak roof height.
The top of the ridge beam m y.
A 1 in 12 roof pitch roof rises 1 inch for every 12 inches of run.
A low slope roof is anywhere from 2 in 12 to 4 in 12.
A flat roof has a slope of 2 in 12 or less.
Per asce 7 the mean roof height h is defined as the average of the roof eave height and the height to the highest point on the roof surface except that for roof angles of less than or equal to 10 the mean roof height is permitted to be taken as the roof eave height.
Use the roof pitch to find the height of a roof peak.
To determine the finished height of the ridge beam add the rise m and the y height.
The pitch of a roof determines the height of the ridge board that runs the length of the house.
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.
If your goal is to only calculate the roof height do not enter any numbers in wall height field and only use building width and roof pitch fields.
Carpenters measure roof pitch as inches of rise per 12 inches of run.
The run always remains constant at 12 inches.
This measurement is best done on a bare roof because curled up roofing shingles will impair your measurement.