How Many Sheets of Drywall Do I Need for a Room?

A 12 × 12 ft room with 8 ft walls needs about 12 sheets of 4 × 8 drywall for the walls and 5 for the ceiling, with 10% extra.

Updated October 7, 2026

The Formula

Wall sheets = (room perimeter × wall height − doors − windows) ÷ sheet area × 1.10
Ceiling sheets = room length × width ÷ sheet area × 1.10

Round each up. A 4 × 8 sheet is 32 sq ft.

Sheets for Common Rooms

The table assumes 4 × 8 sheets, 10% extra, one door (20 sq ft), and two windows (15 sq ft each):

Room	Wall height	Wall area	Wall sheets	Ceiling	Ceiling sheets
10 × 10 ft	8 ft	270 sq ft	10	100 sq ft	4
12 × 12 ft	8 ft	334 sq ft	12	144 sq ft	5
12 × 14 ft	8 ft	366 sq ft	13	168 sq ft	6
14 × 16 ft	8 ft	430 sq ft	15	224 sq ft	8
12 × 12 ft	9 ft	382 sq ft	14	144 sq ft	5

Screws, Mud, and Tape

Screws: USG recommends 16 in spacing on walls and 12 in on ceilings for non-fire-rated work. On framing 16 in on center that’s about 28 screws per 4 × 8 sheet on walls and 35 on ceilings.
Joint compound: about 1 gallon per 100 sq ft (HomeGuide).
Tape: about 10–16 ft per 4 × 8 sheet (HomeGuide).

4 × 8 or Bigger Sheets?

Bigger sheets cover more with fewer seams, and seams are where the finishing time goes. The trade-off is weight and getting long sheets into the room.

The drywall calculator works out sheets, screws, mud, and tape for your room’s exact size and openings.

Frequently Asked Questions

How Many Square Feet Is a Sheet of Drywall?

A 4 × 8 sheet is 32 sq ft, 4 × 10 is 40 sq ft, and 4 × 12 is 48 sq ft.

Should I Subtract Windows and Doors?

Yes, but keep some extra. Cutouts still leave scraps, which is why most estimates add about 10%.

How Many Screws Do I Need per Sheet?

You need about 28 per 4 × 8 sheet on walls and 35 on ceilings, using USG’s spacing of 16 in on walls and 12 in on ceilings with framing 16 in on center.

Sources

Prices are national ballparks checked October 2026. Local prices vary.