LayoutWise

Drywall Calculator

Enter the room size and pick your sheet size. You get the sheets to buy from a real wall-by-wall layout, plus the mud, tape, screws and corner bead to finish them.

Your room

1. Size
Room length
ft
in
Room width
ft
in
Wall height
ft
in
Surfaces to cover
2. Openings & corners

Openings come off the mud, tape and screws. Sheets usually go right over them and get cut out, so they barely change the sheet count.

3. Sheets

Sheets to buy

19

4' x 8'

Area to finish

468 sq ft

32 sq ft openings out

Mud

1 pail

4.2 gal, 3 coats

Screws

563

1 tape roll

⚠ For ceilings use 5/8" board, or 1/2" sag-resistant ceiling board — especially on 24" framing or under insulation.

Sheet layout

Ceiling (sheets run across the joists)Wall A · 12'Wall B · 11'Wall C · 12'Wall D · 11'
Hung horizontally, butt joints staggered Cut from an offcut Door / window cutout

Shopping list

  • ✓Drywall: 19 sheets of 4' x 8' (17 by layout + 10% spare) — 1/2" walls, 5/8" or sag-resistant 1/2" ceiling
  • ✓Joint compound: 1 x 4.5 gal pail (4.2 gal for 3 coats)
  • ✓Paper joint tape: 1 x 500 ft roll (173 ft)
  • ✓Drywall screws, 1 1/4" coarse thread: about 563
  • ✓Corner bead: 2 x 8 ft
  • ✓Utility knife, T-square, drill with dimpler bit, 6" and 10" knives, mud pan, sanding sponge

Mud and tape rates from National Gypsum and USG estimating charts for a level-4, three-coat finish. Done hanging? Plan the next step with the paint calculator.

How much drywall do I need?

Add up the walls: perimeter x wall height, plus length x width for the ceiling. A 12' x 11' room with 8' walls has 368 sq ft of wall and 132 sq ft of ceiling. Dividing by 32 sq ft per 4x8 sheet gives a minimum of 16 sheets — but walls aren't multiples of four feet, so the real number comes from laying sheets out wall by wall. That's what the layout above does, reusing offcuts of 2 ft or more, then adds a few spares.

4x8, 4x10 or 4x12?

Longer sheets mean fewer butt joints — the short-edge joints that are hardest to finish. On a 12-foot wall a 4x12 covers each row in one piece. They're also heavier: a 1/2" 4x12 weighs about 70 lb, so plan on a helper or a lift for ceilings.

Hanging direction and joints

Hang wall sheets horizontally, top row first, so the tapered long edges meet at a comfortable height. Stagger butt joints between rows and keep them off door and window corners, where cracks start. On ceilings, run sheets across the joists.

Mud, tape and screws

MaterialPer 1,000 sq ft of board
Ready-mix joint compound (3 coats)about 9 gallons — two 4.5-gal pails
Paper joint tapeabout 370 ft
Screws, walls (8" edges, 16" field)about 1,000
Screws, ceilings (12" field)about 1,330

Use 1 1/4" coarse-thread screws for 1/2" board on wood studs. Ceilings get 5/8" board or 1/2" sag-resistant ceiling board, especially with 24" framing or blown insulation above.

Painting next? Use the paint calculator — new drywall needs a coat of primer first.