How the Drywall Calculator Works
The estimator multiplies wall length by height, subtracts doors and windows, adds a cutting allowance, and divides by the sheet area. The final sheet count is rounded up to a whole board.
Formula and method
Net wall area = (wall length × height) − openings. Sheets = net wall area × (1 + waste percentage) ÷ (sheet width × sheet height), rounded up.
Tips for better estimates
Use a consistent length unit for the wall, openings area, and sheet dimensions. Add extra material for complex layouts, soffits, returns, ceiling areas, or damaged boards.
Important limitations
This is an area-based estimate for a rectangular wall. It does not design panel layout, framing, fire-rated assemblies, fastener schedules, or local installation compliance.