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Drywall Calculator: Sheets, Screws, Mud and Tape
Calculate how many sheets of drywall you need for a room's walls and ceiling, plus the screws, joint compound and tape to finish it.
How many sheets of drywall do I need?
Add up the wall area (perimeter × height), subtract doors and windows, add the ceiling if you are covering it, then divide by the area of one sheet: 32 sq ft for 4 × 8, 40 for 4 × 10 and 48 for 4 × 12. Add about 10% for cuts.
Example: a 12 × 12 ft room with 8 ft walls has 384 sq ft of wall. Minus a door (21 sq ft) and a window (15 sq ft) leaves 348 sq ft, plus 144 sq ft of ceiling is 492 sq ft. With 10% waste that is 541 sq ft, or 17 sheets of 4 × 8.
Which sheet size is best?
Longer sheets mean fewer joints to tape and sand, so pros often hang 4 × 12 sheets horizontally. But a 4 × 12 sheet of ½ in drywall weighs about 80 lb and is hard to carry up stairs or hang alone. 4 × 8 sheets are easier for DIY work and fit in more vehicles.
- ½ inch is standard for walls and most ceilings.
- ⅝ inch Type X is fire-rated and often required on garage walls shared with the house.
- Moisture-resistant board is used in bathrooms and laundry rooms (use cement board behind shower tile).
Screws, mud and tape
Our estimates use common rules of thumb: about 1.1 screws per sq ft (roughly 32 per 4 × 8 sheet on walls with studs 16 in apart), about 10 gallons of joint compound per 1,000 sq ft for three coats, and about 370 ft of paper tape per 1,000 sq ft. A 4.5 gallon bucket of premixed all-purpose compound covers roughly 450 sq ft.
Frequently asked questions
How many sheets of drywall for a 12x12 room?
With 8 ft walls and the ceiling, a 12 × 12 ft room needs about 17 sheets of 4 × 8 drywall, including 10% waste and after subtracting one door and one window.
How many screws per sheet of drywall?
About 32 screws for a 4 × 8 sheet on walls with studs 16 in apart, and a few more on ceilings.