Drywall Calculator
Enter the room size. You get the number of sheets for the walls and, if you like, the ceiling, after taking out doors and windows.
- Walls
- 384 sq ft
- Ceiling
- 144 sq ft
- Drywall screws
- ≈ 544
How it is calculated
Wall area = 2 × (length + width) × height
Sheets = (walls + ceiling − openings) × (1 + waste) ÷ sheet area
Openings are deducted at 20 sq ft per door and 15 sq ft per window, the usual estimating allowance. Example: a 12 × 10 ft room with 8 ft walls, one door, one window and the ceiling has 437 sq ft of board. With 10 % waste that is 16 sheets of 4 × 8.
Which sheet size?
4 × 8 sheets are easy to carry and fit in most vehicles. Longer 4 × 10 and 4 × 12 sheets mean fewer butt joints to tape on long walls and ceilings, but they are heavy: a ½ in 4 × 12 sheet weighs roughly 60–90 lb depending on the type. Use ½ in on walls and ⅝ in (or sag-resistant ½ in) on ceilings with 24 in framing. Between an attached garage and the house, the IRC (R302.6) calls for at least ½ in gypsum on the garage side, and ⅝ in Type X on a garage ceiling with living space above.
Screws are estimated at about one per square foot of board, 32 for a 4 × 8 sheet at 16 in on center. A 1 lb box of 1¼ in coarse-thread screws holds roughly 250–300.