Drywall Calculator (Sheets Needed)

Number of drywall sheets for walls and optionally the ceiling.

Formula

Sheets = (perimeter × height + ceiling area) × (1 + waste%) ÷ sheet area.

Worked example

Inputs: Room perimeter = 48 ft; Wall height = 8 ft; Include ceiling = 1; Room length (ceiling) = 14 ft; Room width (ceiling) = 10 ft; Sheet width = 4 ft; Sheet length = 8 ft; Waste allowance = 10 %.

Area sq ft	524
Sheets	19

FAQ

Should I subtract doors and windows?

Most estimators do not, because offcuts around openings are rarely reusable; the waste allowance covers it.

Sources

Geometry (volume/area formulas); no external constant needed

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<iframe src="https://provenplaza.com/embed/drywall-calculator.html" width="100%" height="520" style="border:0" loading="lazy" title="Drywall Calculator (Sheets Needed)"></iframe>
<p style="font-size:12px">Calculator by <a href="https://provenplaza.com/drywall-calculator/">Proven Plaza</a></p>

Last reviewed 2026-10-11.