1 8 Roof Slope

The maths behind this number is that it is the square root of rise run 2 1.

1 8 roof slope.

To put it in perspective the angle of this slope would be around 30 degrees. Either way let s see how you can calculate the slope of a roof without using a roof slope calculator. For instance if you travel 3 inches vertically and 3 feet 36 inches horizontally the slope would be 3 36 or 1 12. Coal tar built up roofs however can have a design roof slope of 1 8 12 1 percent but no less.

Slope gradients are written as y x where y is a single unit in rise and x is the run. The most precise way to find the roof s slope is by measuring it from the underside. This means for every 12 horizontal units the roof must rise a minimum of one fourth vertical unit. Since this is a flat roof or nearly flat roof.

This measurement is best done on a bare roof because curled up roofing shingles will impair your measurement. Built up roofs must have a design roof slope of 1 4 12 or greater 2 slope. You can go by the measurements taken by walking the roof. Both numbers must use the same units.

Roof pitch calculator results explained. Slope the slope of a roof is represented as x 12 where x is the number of inches in rise for every 12 inches of run this is very useful information for many purposes especially for roof framing the slope sometimes called pitch is calibrated on speed squares. Angle the angle of a roof is the same as the roof s slope except instead of being. 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 speed square and level can be used to easily find the pitch of a roof. Set the level on the edge of the speed square as shown below then place the heel of the speed square on a rafter or gable edge of the roof. The slope of a roof or pitch is determined by how many inches the roof rises over 1 foot or 12 inches. An example for a steep sloped roof is 8 12.

The pitch of this roof is 4 8 12. Minimum roof slope roof pitch r905 9 1. 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. Access one of the rafters then take the measurement this way.

A roof that rises 8 feet over a 24 foot span was said to have a 1 to 3 pitch. The calculator above can handle much of this math. If the rise is 4 feet over a 24 foot span then the roof pitch was said to be 1 to 6 the pitch can be expressed numerically as a fraction. 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.

0 pitch 1 00x the roof area. Measure with a speed square. This is read as a one in twelve slope.