Roof Cut Factor

When outfitting your residential or commercial structure with products from everlast roofing it s important to know the incline or pitch of your roof.

Roof cut factor. For roof slopes expressed as x in 12 rise in run the roof pitch multiplier is determined by finding the square root of rise run 1. An angle cut is a very common cut needed for constructing rafters for any roof. This roof slope factor table also consists of hip and valley factors to measure the possible hips and valleys. Download the slope chart pdf.

A 7 5 variance of waste on a 30 square roof would be 2 33 squares. Length of the rafter. 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. This measurement is best done on a bare roof because curled up roofing shingles will impair your measurement.

A roof pitch multiplier also called a roof pitch factor is a number that is multiplied by the area covered by a sloped roof to produce the area of the actual surface of the roof. Multi level complex roofs are difficult to estimate. With the saw bevel angle set to 45 cutting hips and creepers at the plumb cut angle will produce correct side angles. On blue prints architects engineers usually display the pitch of a roof in the format shown on the image where number 4 represents a rise and number 12 represents a length.

Note the word large wasn t included. The combination of two numbers are used to display or show the roof pitch. The higher the slope the steeper it is. A a roof with a 6 rise for every 12 run has a 6 per foot or 6 in 12 pitch.

Two most common methods 4 12 or 4 12 are used for marking the pitch of a roof. Knowing how to make this calculation will make your roof construction project easier and will ensure the safety and success of your roofing project once completed. Pitch is thus the ratio of the rise in inches to a 12 inch run and is often expressed using a semicolon for example 6 12. That s 500 to 600 variance on the estimate.

You can consult the following chart to discover the slope factor and hip valley factor. Hip roof framing rafter cut angle template diagram if using a circular saw or compound miter saw set saw bevel angle to 45 to obtain creeper and hip side angles. That s because it is the smaller cut up hip roofs that can often have the highest waste percentage. This way the pitch of the roof and the slope of the roof can be measured.

Roof pitch or slope is a measure of vertical rise to horizontal run expressed in inches per foot.