Walls (in ft.)
Ceiling (in ft.)
Excluded Area (in ft.)
Slopping Wall (in ft.)

Tips on Measuring for Drywall

Before you begin, take the room measurements in the list below round to the nearest foot. If you have sloping walls, follow the special case instructions on how to determine this square footage. A 10 percent waste allowance is automatically added to the total.

1. Wall Height
Measure from floor to ceiling.

2. Wall perimeter for areas you plan to drywall
Measure the length of each wall. Add all length figures together to obtain the total horizontal distance, or perimeter.

3. Ceiling width and length
Omit if you do not plan to drywall your ceiling.

4. Excluded sections
Measure the height and width of each area separately. Add all widths into one total. Add all heights into a second total.

5. Sloping walls
Sloping walls form a triangular wall space. To calculate a triangle’s square footage, multiply the length of the wall at the base of the triangle by its height and divide by 2.

For more on drywall prices, visit our Drywall Hanging Cost Guide.

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  1. richard lee lambert, January 9:

    We got living room to Kitchen I need to know how many pieces of sheetrock I need 14 foot wide by 40 foot long

  2. Adam, March 22:

    I’m wondering how many 12 ft sheets of drywall I’d need for a wall 25 ft x 80 ft

  3. Geovanni canas, October 8:

    Hi, excuse me, I have 2330 square feet in a two-story apartment, how many drywall sheets will I have to buy?

  4. HomeAdvisor, October 12:

    Hi Geovanni – Our True Cost Guide has some information that may be useful in answering your question.

  5. Ray Trujillo, May 9:

    Need to know how much dry wall needed for a 340 square ft room; with an 8 ft height ceiling.

  6. Thomas Jackson, November 19:

    I have a repair job and she says about 100 square ft. How many 4 8 sheeys of drywall do i need for that

  7. Kevin L Martin, December 5:

    How many 4×12ft boards of sheetrock would it take to cover 2000 sq ft All I know is total square footage haven’t seen to measure walls etc thank you

  8. JMH, March 14:

    For the excluded sections, you cannot add lengths and widths together to combine for the area not to be sheetrocked. You will end up with a larger area, or not enough sheetrock.

    If I have 2 windows one 5×5 and another 6×6, you have 25+36 sq ft = 61 sq ft. Adding the length/width together is 11×11 which equals 121 sq ft.

    You have to add the square footage of each section together and get the square root, add that number to both fields in the calculator.

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