Slope is the correct term for the ratio of vertical to horizontal distance on a particular plane of the roof.
Pitch of a roof math.
A roof pitch multiplier also known as a roof pitch factor is a number that when multiplied by the area covered by a sloped roof gives the actual area of the roof.
Roof pitch refers to the measurement of the slope of a roof and you express this as a ratio.
The roof pitch is important in determining the appropriate installation method and how much roofing material will be needed.
Although there s isn t any standard pitch of a roof used on all kinds of sloped roofs you can determine the range of pitches by using a roof angle calculator and by considering factors like the local climate and roofing materials.
Here is a list of common rafter lengths for common pitches.
For instance a 4 12 pitch roof with a 12 foot run would be 12 x 1 055 which equals 12 66 feet.
Roof pitch or slope is a measure of vertical rise to horizontal run expressed in inches per foot.
Roof pitch is used to describe the slope or angle of the roof.
This measurement is best done on a bare roof because curled up roofing shingles will impair your measurement.
The maths behind this number is that it is the square root of rise run 2 1.
Even carpenters often use the terms slope and pitch.
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.
Most people interested in roof pitch are actually measuring the slope which is the most useful measurement when considering roofing material and rainwater.