Professional roofing contractors typically provide estimates of materials needed for roofing, including the number of shingles needed. Simple geometric calculations can provide a rough estimate.
Multiple the length times width for every flat surface on your roof, including dormers. Add together all the totals to get the total square footage.
Shingles are sold in "squares," which are 100 square foot sections of roofing. Unless you are applying shingles directly to an already existing asphalt roof, you probably also need the same amount of underlayment. Divide the roof's total square footage by 100 to determine the number of squares of shingles needed.
Add 10 percent to your total to make sure you have enough shingles for trim.
1. Measure each plane of your roof, length and width. Record the length and width of each plane and then multiply these numbers together to get the square footage of each plane of
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I'm pretty sure you count the number down and the number across and find the area for every face of the roof you have. then add all of the totals together.
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1. Measure the length and width of one bedroom wall. Multiply the width times the height to determine the square footage of that bedroom wall. Repeat this process until you've calculated
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1. Calculate the area of the driveway in square feet and call this number D. For rectangular driveways, D equals length times width (D = L*W) For trapezoidal driveways, D equals the
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