How to Calculate How Much Drywall to Use on a Pitched Ceiling
- 1). Measure the length of the ceiling where the wall meets the ceiling. In this example, it's 25 feet.
- 2). Measure the height of the ceiling from the top of the wall to the peak. In this example, it's 12 feet.
- 3). Multiply the length by the height: 25 feet X 12 feet = 300 square feet.
- 4). Multiply the square footage by two to get both sides of the ceiling: 300 square feet X 2 = 600 square feet. You need 600 square feet of drywall for the ceiling.
- 5). Calculate the number of drywall sheets you need by dividing the area by the size of the sheets. Drywall is usually sold in sheets that measure either 4 feet by 8 feet or 3 feet by 5 feet. Using a 3-by-5 sheet in this example, we know that the area of the 3-by-5 sheet is 15 square feet. Divide the 600 square feet by 15 square feet, and you get 40, which means you need 40 sheets of 3-by-5 drywall to complete this project.
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