48 10 4 8.
Formula roof pitch multiplier.
Let s say it is equal to 1 5 m.
Now divide the rise by the multiplier to get the pitch eg.
Now you re ready to price out the materials.
Measure the rise of your roof.
Use our roof pitch calculator to find the pitch of your roof.
Rafter rise run 1 5 6 2 25 36 38 25rafter 38 25 6 18 m.
If your roof is flat or has no more than a 3 in 12 pitch you can calculate its total square footage by simply multiplying the length by the width.
Here are the equations you may use to solve for the length of the slope and the rafter.
Roof pitch degree table.
Step 1 multiply 20 and 40 which equals 800.
Rafter rise run this formula is from the pythagorean theorem.
Now solving for c in the equation above gives.
Since pitch is the rise over a 12 inch run divide the run by 12 to get the multiplier in this case 120 12 10.
Use the following formula which also describes a right triangle.
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.
100 1 054 105 4ft2.
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.
800 multiplied by 1 16.
Next multiply the footprint of the roof by the multiplier below for your roof pitch to find the overall roof area.
Pitch rise run 1 5 6 25.
You can also calculate roof pitch even without using a roof slope calculator.
For example a 4 12 pitch roof that is 100 square feet.
Step 3 multiply step 1 and step 2 i e.
Calculate the roof pitch as the proportion of rise and run.
Steep roofs measure your house at ground level then add in the roof s overhang for greater accuracy.
If the home measures 20 x 40 and has a 7 12 roof then to calculate the slope of the roof follow these steps.
The formula for the roof pitch multiplier comes from the famous pythagorean theorem.
The pitch of this roof is 4 8 12.
The calculator above can handle much of this math.
Step 2 find the value of 7 12 from the roof slope multiplier table which is 1 16.
Take your area result and multiply it by the pitch multiplier or slope correction factor found in the table above to arrive at the roof s surface area.
