How it is calculated
The wall area (length × height minus openings) is multiplied by the number of sides and layers, plus 5 % for cuts, and divided by the sheet area. Studs are placed at the chosen spacing plus one at the end; plates run along the floor and ceiling. Screws are figured at about one per square foot of drywall.
Sheets = area × sides × layers × 1.05 ÷ sheet areaStuds = wall length ÷ spacing + 1Plates = 2 × wall lengthExample
A 12 ft interior wall, 8 ft high, with drywall on both sides needs 7 sheets of 4 × 8 ft, 10 studs at 16 in on center (80 ft), 24 ft of plates and about 190 screws.
Tips from practice
- Hang sheets horizontally on walls up to 8 ft 1 in to cut down on seams.
- Use moisture-resistant board in bathrooms and fire-rated Type X where code requires it.
- Add studs around doors and wherever cabinets will hang.
Questions and answers
How many sheets of drywall for a 12 × 12 room?
With 8 ft ceilings, the walls take about 12–13 sheets of 4 × 8 ft and the ceiling 5 more.
16 or 24 inches on center?
16 in is standard for walls with 1/2 in drywall. 24 in is common for ceilings with 5/8 in board and for advanced framing.
How many screws per sheet?
About 32 screws for a 4 × 8 sheet on walls at 16 in on center.
Found a mistake in a formula? Write to [email protected]