Plywood & Sheathing Calculator
Enter the area to get how many sheets of plywood, OSB, subfloor, or sheathing you need, with waste built in.
Surface
Works for plywood, OSB, subfloor, and roof or wall sheathing.
You'll need
Area (+10% waste)0 sq ft
Sheets
0
32 sq ft each
Stagger seams and leave a 1/8" gap between sheets for expansion. Round up to whole sheets.
How to estimate sheet goods
Total the area you're covering, add ~10% for waste, and divide by the sheet size (32 sq ft for 4×8). Stagger the seams and leave a small expansion gap between sheets.
Sheet a whole floor or roof from a scan
ProBuildCalc turns your iPhone's LiDAR scanner into a job-site measuring kit — walk the space and it captures the square footage, material takeoff, and a blueprint automatically. No tape measure, no graph paper.
Plywood calculator FAQ
- How many sheets of plywood do I need?
- Divide the total area (plus ~10% waste) by the sheet size — 32 sq ft for a 4×8 sheet, 40 for a 4×10. A 400 sq ft floor at 10% waste needs about 14 sheets of 4×8.
- What's the square footage of a sheet of plywood?
- A standard 4×8-ft sheet is 32 square feet. A 4×10-ft sheet is 40 square feet.
- How much waste should I add for sheathing?
- Add about 10% for straightforward walls, floors, and roofs, and 15% for cut-up areas with lots of openings or angles.
- Does this work for OSB and subfloor?
- Yes — plywood, OSB, subfloor, and wall or roof sheathing all come in the same 4×8 and 4×10 sheet sizes, so the count is the same.