Get a complete drywall shopping list for a room: sheets for the walls and ceiling (each with its own sheet size), screws, joint compound, paper tape, and corner bead. Openings are subtracted, a waste allowance is added, and the finishing materials come from published USG coverage rates and the Gypsum Association fastener spacing, so the numbers match what the manufacturers expect.
Framing first? The stud wall calculator counts studs and plates, and the insulation calculator sizes the batts that go in before the board. Once the mud is dry, the paint calculator tells you how much primer and paint to buy. Tiling a bathroom wall instead of painting it? The tile calculator counts tiles and boxes for the same wall area.
Frequently asked questions
How many sheets of drywall do I need for a 12×12 room?
A 12×12 room with 8 ft walls has 384 sq ft of wall and a 144 sq ft ceiling. Subtract a door (about 21 sq ft) and a window (about 15 sq ft) and the walls need 348 sq ft. With 10 % waste that is about 383 sq ft, or 12 sheets of 4×8 (32 sq ft each). The ceiling needs 144 × 1.1 ÷ 32 = 4.95, so 5 sheets of 4×8 or 4 sheets of 4×12. Always round up to whole sheets.
How many drywall screws per sheet?
The Gypsum Association's application standard (GA-216) spaces screws no more than 12 in apart on ceilings and 16 in apart on walls when framing is 16 in on center. That works out to roughly one screw per square foot, so about 32 screws for a 4×8 sheet and 48 for a 4×12. The calculator uses one per square foot of board hung, which is slightly generous on walls — screws are cheap and you will drop a few. Use 1-1/4 in coarse-thread screws for 1/2 in board on wood studs.
How much joint compound do I need?
USG rates its Sheetrock all-purpose ready-mixed joint compound at approximately 10 gallons per 1,000 sq ft of drywall. That covers embedding the tape plus the fill and finish coats over joints, screws, and corner bead. It comes in 4.5 gallon pails, so a typical 12×14 room with a ceiling (about 550 sq ft of board once a door and a window are deducted) needs roughly 5.5 gallons — two pails. Lightweight compounds cover a little more per gallon; skim-coating a whole wall takes far more. Setting-type compound in bags is measured by weight, so check its bag for coverage.
How much drywall tape do I need?
USG estimates about 370 ft of paper tape per 1,000 sq ft of board, which is roughly 12 ft per 4×8 sheet once you account for shared edges and inside corners. Paper tape comes in 250 ft and 500 ft rolls. Mesh tape is an alternative for flat seams with setting-type compound, but paper tape is stronger in inside corners. Outside corners get metal or paper-faced corner bead instead of tape, which is why the calculator counts bead separately. Buy an extra roll — tape is inexpensive and running out mid-seam is annoying.
What size drywall should I use?
Use the longest sheet you can handle so there are fewer joints to finish. On 8 ft walls, 4×8 sheets hung horizontally leave one seam at mid-height; 4×12 sheets reduce the butt joints along a long wall. On 9 ft or 10 ft walls, 4×9 or 4×10 sheets hung vertically avoid a horizontal seam entirely. Ceilings usually get 5/8 in board (or 1/2 in sag-resistant) to prevent sagging, while walls take 1/2 in. Use moisture-resistant board in bathrooms and cement board behind tile in showers.