Roof Slope 1 4 Over 12 Architectural Note

4 12 is the incline of the roof expressed as.

Roof slope 1 4 over 12 architectural note.

Note the roof material. Slopes greater than 18 12 are found on a frame roofs and some mansard style. 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. You can measure the roof slope on the bottom side.

Roof slopes are most commonly defined by the rise over run ratio. 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. See low slope roofing. A roof that rises 4 inches for every 1 foot or 12 inches of run is said to have a 4 in 12 slope.

For example if you measure 4 inches the pitch of your roof is 4 12. Some sources consider low slope to include 3 12 pitch roofs. 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. Low slope roofs are from 0 to 3 12 in pitch.

You can go by the measurements taken by walking the roof. The table below shows common roof pitches and the equivalent grade degrees and radians for each. A 4 in 12 slope can be expressed as the ratio of. This will give you the rise over run or pitch.

The slope ratio represents a certain amount of vertical rise for every 12 inches of horizontal run. Note that roof pitch is sometimes used in parallel with roof slope. 1 12 roof pitch angle 4 76 degrees. However roof pitch is technically measured and defined differently and will not be discussed here.

0 pitch 1 00x the roof area. Most roof s have a pitch in the 4 12 to 9 12 range. However you can only use this pitch with built up roofing or specialized synthetic roofing. The minimum pitch for a roof is 1 4 12 which translates to 1 4 inch rise to 12 inches of run.

If a roof rises 1 in a length of 12 this is 1 12 roof pitch. If the rise is 6 inches for every 12 inches of run then the roof slope is 6 in 12 the slope can be expressed numerically as a ratio. I e 4 inches of rise per 12 inches one foot of run. 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.

If the rise is 4 feet over a 24 foot span then the roof pitch is 1 to 6 is expressed as a ratio and in inches per foot.