Plywood and OSB Sheet Calculator
Sheets are bought whole — you cannot buy two thirds of a sheet. This calculator converts your project area into the number of 4×8, 4×10 or 5×5 sheets to order, with the waste factor contractors actually use.
Results
Enter your measurements above and press Calculate.
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Questions people ask
How many 4x8 plywood sheets do I need?
Divide your project area by 32 square feet, then add the waste factor. A 12 × 16 foot floor is 192 square feet, which is 6 sheets at zero waste or 7 sheets at the standard 10 percent.
What is the difference between plywood and OSB?
OSB is oriented strand board — cheaper, and structural sheathing walls and roofs only. Plywood holds fasteners better and is the right choice for subfloor, cabinetry and anything that will be visible or wet. Use exterior-rated glue on any sheathing.
How much waste should I add for plywood?
Ten percent for walls and roofs with simple layouts, 15 to 20 percent for floors with many cuts or a complex pattern. Every sheet edge must be supported, so offcuts rarely fit another area.
Can I use 5x5 sheets instead of 4x8?
Yes, and for small rooms they cut with far less waste. Check that your sheathing supplier carries them — 4×8 is far more common and cheaper, and many rental nail guns are set up for it.
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