Drywall & Paint Takeoff
Estimate drywall sheets and paint gallons for a surface from its width and height.
- Drywall: 3 bare 4 × 8 ft sheets, or 4 with ~10% waste (typical over-order).
- Paint assumes ~350 sf/gal — a typical interior value; check the product label.
- Area is gross (no deductions) — subtract doors and windows for a tighter estimate.
How the estimate works
Area is just width × height. Drywall is that area divided by
the sheet's coverage (a 4 × 8 ft sheet is 32 sf), rounded up — plus a line
with a typical ~10% waste allowance for cuts and breakage.
Paint uses a typical ~350 sf per gallon coverage and shows one- and two-coat totals. Real coverage varies by product, surface, and porosity, so treat it as a starting point and check the can's label.
The area is gross — it doesn't deduct doors and windows. For a single room's walls, run the calculator once per wall (or use the total perimeter × height), and subtract large openings if you want a tighter number.
Frequently asked questions
How many drywall sheets do I need?
Divide the surface area (width × height) by a sheet's coverage — a 4 × 8 ft sheet is 32 sq ft — round up, then add about 10% for cuts and breakage. A 320 sq ft wall needs 10 sheets before waste, about 11 with it.
How much paint do I need for a room?
Figure roughly 350 sq ft of coverage per gallon per coat: divide your surface area by 350 for one coat and double it for two. Actual coverage varies with the product, surface, and porosity, so check the can's label.
Does this deduct doors and windows?
No — the area is gross (width × height) and doesn't subtract openings. For a tighter number, subtract large doors and windows or run each wall separately; a little overage is usually welcome for waste and touch-ups.