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.
1 2 pitch roofing.
Pitch is the term used to describe the angle slope or slant of your roof.
The pitch can be expressed numerically as a fraction.
This measurement is best done on a bare roof because curled up roofing shingles will impair your measurement.
The exact roof slope in degrees is given by the arctangent.
Roof pitch defined and explained.
Thus pitch is typically greater in areas of high rain or snowfall.
In degrees 10 2 in 12 or 1 in 6 is considered a minimum.
A pitch over 9 12 is considered a steep slope roof between 2 12 and 4 12 is considered a low slope roof and less than 2 12 is considered a flat roof.
The pitch fraction represents a certain amount of vertical rise over the entire span.
1 pitch 1 01 2 pitch 1 02 3 pitch 1 03 4 pitch 1 05 5 pitch 1 085 6 pitch 1 12 7 pitch 1 16 8 pitch 1 21 9 pitch 1 25 10 pitch 1 31 11 pitch 1 36 12 pitch 1 42.
Most roof s have a pitch in the 4 12 to 9 12 range.
Or the colon can replace the slash as in 2 12 or 7 12.
The table below shows common roof pitches and the equivalent grade degrees and radians for each.
A pitch of 2 12 is the minimum pitch for shingles made of asphalt so your roof just barely makes the cut off for one of the most popular roofing material options.
Definitions vary on when a roof is considered pitched.
Resilient asphalt shingles lie much flatter to the substrate than slate tile and concrete which keeps water from being easily blown under them.
0 pitch 1 00x the roof area.
Arctan 3 12 14 0 the primary purpose of pitching a roof is to redirect water and snow.
For example given a roof with a rise of 4 feet and a span of 24 feet the pitch is 1 to 6 pitch which can be expressed as the fraction of 1 6.
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.
A 12 to 24 pitch is expressed as 1 2.
The maths behind this number is that it is the square root of rise run 2 1.
Since this is a flat roof or nearly flat roof.
You can go by the measurements taken by walking the roof.
But the taller profiles like standing seam and pbr shown below can be installed on roofs with as low as 1 4 or 1 2 in 12 pitch.