Estimate how many sheets of drywall (also called plasterboard, gypsum board or Sheetrock) you need to hang a room. Enter the total length of the walls, their height and any ceiling area; standard doors and windows are subtracted for you.
Formula
Sheets = ⌈ (Wall length × Height − Openings + Ceiling) × (1 + Waste) ÷ Sheet area ⌉
A door is taken as 21 ft² (about 2 m²) and a window as 15 ft² (about 1.4 m²).
Worked example
A room with 48 ft of walls, 8 ft high, one door and two windows: 384 − 21 − 30 = 333 ft². With 10% extra that is 366 ft², or 12 sheets of 4 × 8 ft drywall and about 370 screws.
Frequently asked questions
How many sheets of drywall do I need for a 12 × 12 room?
Four 12 ft walls, 8 ft high, are 384 ft² — about 12 sheets of 4 × 8 before subtracting doors and windows, plus 5 more if you also cover the 144 ft² ceiling.
Should I hang drywall horizontally or vertically?
On walls, hanging sheets horizontally usually means fewer seams and stronger joints. Ceilings go up first, then the walls.
Last updated · Calculations checked by automated tests· Editorial policy