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.

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. This means for every 12 horizontal units the roof must rise a minimum of one fourth vertical unit. A speed square and level can be used to easily find the pitch of a roof. For instance if you travel 3 inches vertically and 3 feet 36 inches horizontally the slope would be 3 36 or 1 12.

Minimum roof slope roof pitch r905 9 1. 0 pitch 1 00x the roof area. Coal tar built up roofs however can have a design roof slope of 1 8 12 1 percent but no less. You can go by the measurements taken by walking the roof.

Built up roofs must have a design roof slope of 1 4 12 or greater 2 slope. Calculating a slope gradient. 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. 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.

Roof pitch calculator results explained. This measurement is best done on a bare roof because curled up roofing shingles will impair your measurement. Access one of the rafters then take the measurement this way. Measuring the slope from the rafters.

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. Both numbers must use the same units. The calculator above can handle much of this math.

The pitch of this roof is 4 8 12. To put it in perspective the angle of this slope would be around 30 degrees. The slope of a roof or pitch is determined by how many inches the roof rises over 1 foot or 12 inches. The most precise way to find the roof s slope is by measuring it from the underside.

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. An example for a steep sloped roof is 8 12. Since this is a flat roof or nearly flat roof. A roof that rises 8 feet over a 24 foot span was said to have a 1 to 3 pitch.

Measure with a speed square. Slope gradients are written as y x where y is a single unit in rise and x is the run. 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.