Roof Pitch Factor Multiplier

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.

Roof pitch factor multiplier.

This roof pitch chart will give you your multiplier. So the actual roof surface if it were laid down flat on the ground would be 1 118 times larger than the footprint of the roof. This will give you the rise over run or pitch. 2280 1900 380 feet added for pitch.

For example if you measure 4 inches the pitch of your roof is 4 12. And for a roof with a slope of 6 12 that number 1 118 is your roof slope multiplier. The headache of using pythagoras and trigonometry can be spared by making use of these charts. If you know the pitch of a roof you can use the numbers in the following pitch table to do the following.

It is sometimes called the roof pitch multiplier. A 10 slope roof should not be confused with a 10 pitch roof as a 10 slope roof means that the roof rises by ten inches for every foot of run. If the home measures 20 x 40 and has a 7 12 roof then to calculate the slope of the roof follow these steps. Determine how many square feet of roof area a building has by measuring from the ground.

Take the area of the roof s footprint say it s 5 000 square feet and multiply 5 000 by 1 118. 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. Determine how many square feet of roof area a building has by measuring blueprints or plans. The roof slope factor chart also consists of conversion factors to determine the slope of the roof.

Step 1 multiply 20 and 40 which equals 800. Step 2 find the value of 7 12 from the roof slope multiplier table which is 1 16.