Estimate siding square footage and squares from exterior wall dimensions, openings and waste.
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A net wall area of 1,800 square feet equals 18 siding squares before waste.
Estimate siding square footage and squares from exterior wall dimensions, openings and waste. The result is intended for quick estimates, checking arithmetic and comparing scenarios. When a result affects a contract, tax filing, medical decision, building-code requirement or other high-stakes situation, verify the result with the appropriate professional or authoritative source.
The calculator first subtracts the area of doors and windows from the gross exterior wall area. It then applies the waste percentage to the remaining wall area. A waste allowance can help account for cuts, damaged pieces and layout losses, but the appropriate allowance varies by siding material and project geometry.
With 2,000 square feet of gross wall area, 200 square feet of doors and windows, and 10% waste, the net wall area is 1,800 square feet. Adding 10% gives 1,980 square feet, or 19.8 siding squares. Product packaging, overlap, starter strips and manufacturer instructions may affect the amount actually purchased.
Start with 2,000 square feet of gross wall area; after subtracting 200 square feet of openings, 10% waste gives 1,980 adjusted square feet.
Siding is often priced by the square, which is 100 square feet.
Trim, starter strips, openings, gables, waste and package coverage must be planned separately.
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Estimate siding square footage and squares from exterior wall dimensions, openings and waste.
Net siding area = gross wall area − doors/windows. One siding square commonly represents 100 square feet.
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