Roofing Square Footage Multiplier

Multiply by the square footage of a single floor of your house.

Roofing square footage multiplier. 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. For example a 4 12 pitch roof that is 100 square feet. Multiply 20 and 40 which equals 800. Determine how many square feet of roof area a building has by measuring blueprints or plans.

Multiply the area by the pitch multiplier to get the roof s square footage. Roof surfaces are measured in squares a square is an area of roof which measures 100 square feet. Find the value of 7 12 from the roof slope multiplier table which is 1 16. In the united states a run of 12 inches 1 foot is used and pitch is measured as the rise of the roof over 12 inches.

Steep roofs measure your house at ground level then add in the roof s overhang for greater accuracy. Then take the product of these two dimensions and multiply it by your pitch multiplier. It is often compared to slope but is not exactly the same. 100 1 054 105 4ft 2.

The number you get will be an accurate estimate of how much area you have to cover for your roofing project. Multiply step 1 and step 2 i e. The average roof is 3 000 square feet or around 30 squares. Determine how many square feet of roof area a building has by measuring from the ground.

Roof pitch is the measurement of a roof s vertical rise divided by its horizontal run. For the total square footage of the roof. Next multiply the footprint of the roof by the multiplier below for your roof pitch to find the overall roof area. Plane 1 plane 2 24 000 sq.

800 multiplied by 1 16. Many homes have an asphalt shingle roof but some have wood metal tile and slate which can be more expensive. A roof pitch multiplier also called a roof pitch factor is a number that is multiplied by. If the home measures 20 x 40 and has a 7 12 roof then to calculate the slope of the roof follow these steps.

Roofing material is estimated by the square which is equal to 100 square feet. This roof pitch chart will give you your multiplier. First multiply the length by the width.