How to use the Siding Calculator

Estimate siding square footage and 100-square-foot siding squares after openings and waste.

Calculation formula

Net siding area = max(wall area − openings, 0) × (1 + waste%); siding squares = net square feet ÷ 100.

Recommended steps

1. Enter values using the units shown beside each field.
2. Review whether the example assumptions match your situation.
3. Run the calculator and compare the key metrics.
4. Use the source data or official rates when precision matters.

Known limitations

Trim, starter strips, overlaps, different panel exposure and local installation requirements are excluded.