Drywall Calculator
Calculate drywall sheets for any room — walls and ceiling — plus the joint compound, tape and screws to finish the job, with a 10% waste factor built in.
Standard practice: don't subtract openings under ~30 sq ft — offcuts rarely reuse. We deduct half of each.
You might also need:Paint Calculator·Tile Calculator
How to estimate drywall
sheets = (total area × 1.10 waste) ÷ sheet size, rounded up
Estimators deliberately under-subtract door and window openings — the cutouts are rarely usable elsewhere, and running short means a supply run mid-hang. This calculator deducts just 10 sq ft per opening (about half a door) and adds 10% waste on top.
Finishing materials per 1,000 sq ft of drywall
| Material | Quantity |
|---|---|
| Joint compound (ready-mix) | One 4.5-gal bucket (~62 lb) |
| Joint tape | ~370 linear ft |
| Screws (1¼″ coarse) | ~5 lb (1,000 screws) |
| Corner bead | Per outside corner, floor-to-ceiling |
Hanging tips
- Hang horizontally on walls: it bridges more studs, stiffens the wall and puts the long seam at a comfortable finishing height.
- Ceilings first: wall sheets then support the ceiling edges.
- Stagger the joints: avoid four-corner intersections — they crack.
- Once it's hung and finished, size the primer and topcoats with the paint calculator.
Frequently asked questions
What size drywall sheets should I use?+
4×8 ft sheets (32 sq ft) are the standard DIY choice — manageable weight and fit through doorways. 4×12 sheets (48 sq ft) mean fewer joints to tape and are preferred by pros on big open walls. Use ½-inch thickness on walls, ⅝-inch on ceilings and garage walls (fire code).
How many drywall sheets do I need for a 12x12 room?+
A 12 × 12 ft room with 8 ft ceilings has 384 sq ft of wall and 144 sq ft of ceiling — 528 sq ft total. With 10% waste, that is about 19 4×8 sheets (12 walls-only).
How much joint compound per sheet of drywall?+
Plan on about 0.05 lb of ready-mix joint compound per square foot — roughly one 4.5-gallon bucket (61.7 lb) per 1,000 sq ft of drywall for a full three-coat finish.
How many screws per sheet of drywall?+
About 32 screws per 4×8 sheet on walls (one per stud every 16 inches, rows every 12 inches) and 36 on ceilings. One pound of 1¼-inch coarse screws (~200 screws) hangs about 6 sheets.
How much does drywall cost to install?+
Materials run $0.50–$0.80 per square foot (sheets, mud, tape, screws). Professionally hung and finished, expect $1.50–$3.50 per square foot depending on finish level and ceiling height.