Drywall Calculator

Wall area is the perimeter times the ceiling height; add length × width again if you are also hanging the ceiling. Divide by the area of one sheet and add about 10% for cuts. A 4 × 8 sheet is 32 sq ft, a 4 × 12 is 48 — larger sheets mean fewer seams to tape, which is where the real labor hides.

The perimeter is 52 ft, so at 8 ft high the walls are 416 sq ft, and the ceiling adds 168 for 584 sq ft total. With 10% waste that is 643 sq ft, or 21 sheets of 4 × 8. Expect about 6 gallons of joint compound, some 234 ft of tape, and roughly 700 screws — the consumables people forget until the store is closed.

Drywall is cut from full sheets, and the piece removed for a doorway is usually too narrow or too short to use anywhere else. Standard practice is to hang straight over an opening and cut it out afterward, which gives cleaner edges and avoids a seam at the corner where cracks always start. So order on gross area and treat openings as part of the waste allowance.

Half-inch board is standard for walls and ceilings on 16-inch framing; 5/8 inch is used for ceilings on 24-inch spacing (it sags less), for fire-rated assemblies, and wherever code calls for Type X. Moisture-resistant board belongs in bathrooms, and cement board — not drywall of any kind — goes behind tile in a shower. Ceilings are hung before walls, so the wall sheets support the ceiling edge.

Hanging a room takes an afternoon; finishing it takes days, because each of the three compound coats has to dry before sanding. Budget roughly a gallon of all-purpose compound per 100 sq ft across all coats, use paper tape at inside corners and metal or composite bead on outside ones, and prime before painting — bare joint compound absorbs paint at a completely different rate from paper facing.