Drywall calculator
Room dimensions in — sheets, mud, tape and screws out. Ceiling optional, openings subtracted, 10% waste added.
| Surface area (with 10% waste) | |
|---|---|
| Sheets | |
| Joint compound, gallons | |
| Joint tape, ft | |
| Screws (≈32/sheet) |
Openings: door counted as 21 sq ft, window as 15 sq ft. Tape ≈ 1 ft per 2 sq ft of board; mud ≈ 0.05 gal/sq ft for three coats.
FAQ
4×8 or 4×12 sheets?
4×12 means fewer seams and less taping on long walls, but sheets are heavy and awkward on stairs. 4×8 is the default for DIY and small rooms.
How much joint compound per sheet?
Roughly 0.05 gallons of ready-mix per square foot of drywall for a full three-coat finish — about a gallon and a half per 4×8 sheet.
Do I subtract doors and windows?
Small openings are usually ignored (they roughly offset the waste). This calculator subtracts them explicitly and then adds a 10% waste factor.