The triangle diagram will be re drawn to scale with all dimensions marked.
1 2 inch slope roof.
Most roof s have a pitch in the 4 12 to 9 12 range.
Slope conversion tables 1 4 1 2 3 4 1 1 1 4 1 1 2 1 3 4 2 2 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 0 25 0 50 0 75 1 00 1 25 1 50 1 75 2 00 2 25 3 4 5 6 7 8 9 10.
That means the roof doesn t shed water as easily as steeper roofs which is why choosing the right type of roofing material is so important.
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.
Drag sliders to animate the results and diagram.
Flat 0 in 12 to 2 in 12.
Low pitched roofs are generally difficult to maintain and you need special materials to prevent leaks.
The most common rafter spacing is 24 inches and 5 8 inch plywood is recommended for that.
A roof that rises 4 inches for every 1 foot or 12 inches of run is said to have a 4 in 12 slope.
These roofs have a pitch less than 4 12.
Enter run the flat level length then click pitch angle or rise to select then enter other known dimension angle or pitch.
The table below shows common roof pitches and the equivalent grade degrees and radians for each.
Low slope 2 in 12 to 4 in 12.
If a roof slope rises say 4 inches when measured 12 inches along the bottom of a horizontal roof truss.
Generally these roofs have a pitch from 1 2 12 to 2 12 from 4 2 to 16 7.
Generally such roofs have a pitch ranging from 1 2 12 to 2 12.
For example a pitch 1 12 means that per every twelve yards of building length the rise will be equal to one yard.
A 2 12 roof slope means your roof has 2 inches of vertical drop for every 12 inches of horizontal distance.
For rafters spaced 20 or more inches apart 1 2 or 5 8 inch plywood is recommended.
This measurement is best done on a bare roof because curled up roofing shingles will impair your measurement.
We can divide roofs into the following categories.
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 slope ratio represents a certain amount of vertical rise for every 12 inches of horizontal run.
Roof slopes slope rise run in inches conventional slope 4 in 12 and up.
Flat roofs which aren t perfectly flat require a small slope to allow for water runoff.
Simply put it s a shallow roof.
Roof slopes are most commonly defined by the rise over run ratio.
