Drywall Calculator
Calculate sheets of drywall (plasterboard), tape, and joint compound for walls and ceilings. Works in metric or imperial.
Results
How to Calculate Drywall
Calculate wall area (perimeter x height) plus ceiling area if applicable. Divide total square footage by sheet size (32 sq ft for 4x8). Add 10-15% for waste and cuts. You'll also need about 3.5 lbs of joint compound and 1 roll of tape per 100 sq ft.
Frequently Asked Questions
How many sheets of drywall (plasterboard) do I need?
A 3.6 x 3.6 m (12 x 12 ft) room with 2.4 m ceilings needs about 12 sheets for walls plus 4-5 for the ceiling. Standard sheet sizes are 1200 x 2400 mm (4x8 ft) or 1200 x 2700 mm.
What size sheets should I use?
1200 x 2400 mm (4x8 ft) is standard worldwide. Longer sheets (2700 mm / 3000 mm or 10-12 ft) reduce joints on taller walls. Use 12.5 mm (1/2 in) thickness for walls and 9.5 mm (3/8 in) for ceilings with close joist spacing.