Drywall calculator: how many sheets of drywall do I need?
Enter the room size, openings and sheet size. The calculator works out wall and ceiling area, adds waste, rounds up to whole sheets, and estimates joint compound buckets and tape rolls.
Price this job as an estimate in Quotesprig (free)
Common sizes, worked out
4 × 8 ft sheets, 8 ft walls, 1 door, 1 window, ceiling included, 10% waste. Every number below comes from the same calculator code as the tool above.
| Job | Board area | 4×8 sheets | Joint compound | Joint tape | Labour |
|---|---|---|---|---|---|
| 10 × 10 ft room | 384 sq ft | 14 sheets | 1 bucket | 1 roll | 10.5 hr |
| 12 × 12 ft room | 492 sq ft | 17 sheets | 2 buckets | 1 roll | 12.8 hr |
| 12 × 16 ft room | 604 sq ft | 21 sheets | 2 buckets | 1 roll | 15.8 hr |
| 20 × 20 ft garage | 1,004 sq ft | 35 sheets | 3 buckets | 1 roll | 26.3 hr |
| 24 × 24 ft garage | 1,308 sq ft | 45 sheets | 4 buckets | 2 rolls | 33.8 hr |
Assumptions you can change
Starting values: waste allowance 10 %, area per door 21 sq ft, area per window 15 sq ft, joint compound: area per bucket 400 sq ft, tape per unit of area 0.4 ft per sq ft, tape per roll 500 ft, hours per sheet (hang + finish) 0.75 hr. They are typical starting points, not rules: use the numbers on your product labels and your own production rate.
FAQ
How many sheets of drywall for a 12x12 room?
For a 12 × 12 ft room (4 × 8 ft sheets, 8 ft walls, 1 door, 1 window, ceiling included, 10% waste): board area 492 sq ft; 4×8 sheets 17 sheets; joint compound 2 buckets; joint tape 1 roll. Change any input above for your own job.
4x8 or 4x12 sheets?
4×12 sheets mean fewer joints to tape on long walls but are heavier to handle; switch the sheet size in the calculator to compare counts.
Does it include joint compound and tape?
Yes: buckets from the area per bucket and tape rolls from the tape per unit of area, both editable assumptions.
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