Drywall Sheets Calculator
Calculate how many drywall sheets you need for walls and ceilings, including waste and screw count.
What this calculates
Drywall sheets come in 4×8, 4×9, 4×10, and 4×12 sizes. Bigger sheets mean fewer seams to tape and finish, but they're heavier and harder to handle solo. This calculator figures the sheet count for a room based on total wall + ceiling area, with a 10 % waste allowance and screw count estimate.
Formula & how it works
Total area = wall_perimeter × ceiling_height + room_floor_area (ceiling). Sheet count = total_area ÷ sheet_area × (1 + waste). Screws: ~32 per sheet (16 inch on-center on edges and field). Mud and tape: 1 gallon mud per 100 sq ft, 250 ft tape per 500 sq ft.
Worked example
10×12 room, 9 ft ceilings. Walls: 44 × 9 = 396 sq ft. Ceiling: 120 sq ft. Total: 516 sq ft. Using 4×8 (32 sq ft each): 516 / 32 × 1.10 ≈ 18 sheets. Screws: 18 × 32 = 576 screws. Mud: ~5 gallons. Tape: ~260 ft.
Frequently asked questions
1/2 inch or 5/8 inch?
1/2 inch standard for walls. 5/8 inch fire-rated required between garage and house, in some commercial situations. 5/8 inch slightly stiffer and better acoustically. Ceilings often 5/8 for sag resistance.
Mold-resistant drywall?
Worth it for bathrooms and basements. Green or purple boards. Costs 30-50 % more than regular but worth not having to tear out moldy walls in 10 years.
Hanging tips?
Hang ceiling first. Use a drywall lift for ceilings (rentable). Stagger seams. Use a router or rotary tool for outlet boxes. Two people speed it up dramatically.
How long does mudding take?
Three coats: tape coat → block coat → skim. Each needs 24 hours drying. So 3 days minimum for finishing. Add sanding day. Reality: a small bathroom takes a long weekend.
Related calculators
- Square FootageCalculate the area of a room or surface in square feet or square meters. Supports rectangle, triangle, and circle shapes.
- Paint CalculatorCalculate how much paint you need for a room. Accounts for wall area, coats, doors, windows, and typical 350 sq ft/gallon coverage.
- Board FeetCalculate board feet for any quantity of lumber. Useful for hardwood pricing, framing estimates, and project cost-out.