Drywall Calculator
Calculate sheets, joint compound, tape, and screws for your project.
Results
Total Area —
Sheets Needed —
Joint Compound —
Joint Tape —
Drywall Screws —
Includes 10% waste factor. Screws estimated at 1 per sq ft (16" OC framing).
Advertisement
How to Calculate Drywall
To figure out how many sheets of drywall you need, calculate the total wall (and optionally ceiling) area, subtract openings, add waste, then divide by sheet size.
Drywall Formula
Wall Area = Perimeter × Height
Subtract: Doors (21 sq ft each) + Windows (15 sq ft each)
Sheets = (Area × 1.10 waste factor) / Sheet Size (sq ft)
Subtract: Doors (21 sq ft each) + Windows (15 sq ft each)
Sheets = (Area × 1.10 waste factor) / Sheet Size (sq ft)
Sheet Sizes
- 4' × 8': Standard size, easiest to handle. Best for 8' ceilings.
- 4' × 10': Fewer seams on taller walls. Best for 9-10' ceilings.
- 4' × 12': Best for large areas — reduces seams by 33% vs 4×8. Requires two people.
Drywall Thickness Guide
- 1/4": Curved walls, covering old surfaces
- 3/8": Budget option for ceilings with 16" OC framing
- 1/2": Standard for walls and ceilings (most common)
- 5/8": Required for garage/house firewall, soundproofing, ceiling with 24" OC framing
Supplies You'll Need
- Joint compound: ~0.05 gallons per sq ft (one 4.5-gallon bucket per 375 sq ft)
- Joint tape: ~1 foot of tape per sq ft of drywall
- Screws: ~1 screw per sq ft with 16" OC framing (32 screws per 4×8 sheet)
- Corner bead: 1 piece per outside corner
For a smooth finish, invest in a quality drywall tool kit that includes taping knives, a mud pan, and a sanding block. You can also order drywall sheets at Lowe's for delivery to save a trip.