For Roof Slopes From 2 12 To 4 12

0 7 x 12 8 4.

For roof slopes from 2 12 to 4 12. Find the arctangent of the resulting value. Giving you a slope of 8 4 in 12 or. Divide the percentage number by 100. Roof pitch is a term describing how steep or flat your roof slope is.

This will give you the rise over run or pitch. For a slope of 55 55 divided by 100 0 55. For example if you measure 4 inches the pitch of your roof is 4 12. Two most common methods 4 12 or 4 12 are used for marking the pitch of a roof.

If this isn t practical then perform the same measurement on the underside of. I e 4 inches of rise per 12 inches one foot of run. If a roof slope rises say 4 inches when measured 12 inches along the bottom of a horizontal roof truss the roof slope is said to be 4 12. The combination of two numbers are used to display or show the roof pitch.

Simply locate a roof rafter board place the end of the level against the bottom edge and measure from the 12 inch mark vertically to the bottom edge of the rafter. Roof slopes are most commonly defined by the rise over run ratio. This measurement is best done on a bare roof because curled up roofing shingles will impair your measurement. The table below shows common roof pitches and the equivalent grade degrees and radians for each.

55 slope is equal to a slope of 28 81. 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. Most roof s have a pitch in the 4 12 to 9 12 range.