This measurement is best done on a bare roof because curled up roofing shingles will impair your measurement.
How to get a pitch on a roof.
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 is used to describe the slope or angle of the roof.
Ideally you will have safe access to your roof from inside the building.
The tools required will be a contractor s level at least 24 inches long and a tape measure.
Here s an easy safe way to determine the pitch from inside your attic.
How to measure roof pitch.
Roof pitch or slope is a measure of vertical rise to horizontal run expressed in inches per foot.
The 7 means that the roof rises 7 for every 12 it runs.
For a roof with the ridge above one wall the span is the same as the run.
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.
We get a 12 run with 5 3333 or 5 4 rise well that is our roof pitch 5 4 in 12.
The roof pitch is important in determining the appropriate installation method and how much roofing material will be needed.
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.
Roof pitch refers to the measurement of the slope of a roof and you express this as a ratio.
Carpenters use special conversion charts to estimate the roofing material required based on the slope and shape.
You can also calculate roof size using pitch without using the pythagorean theorem.
Also referred to as roof slope or roof slant so what does the 7 12 in the example to the right mean.
Roof pitch calculator is determined by the number of inches it rises vertically for every 12 inches it extends horizontally.
If not you will need to make your measurement from on top of the roof itself or at the edge of the roof with a ladder.
Measuring a roof pitch.
For more complex roofs you may need to calculate it section by section.
To measure the roof pitch you ll need an 18 or 24 inch level a tape measure and a pencil.
How to determine or calculate roof pitch or roof slope.
The maths behind this number is that it is the square root of rise run 2 1.
Knowing the pitch of your roof is useful when designing an addition installing skylights or cutting new rake boards.