How siding area is calculated
Multiply building perimeter by wall height, subtract openings and add the selected waste allowance.
Wall area = 2 × (Length + Width) × Height
What is a siding square?
A siding square is a material-coverage unit equal to 100 square feet.
Complex elevations
Gables, dormers and irregular wall shapes should be measured separately for a more accurate estimate.
Frequently asked questions
How many square feet are in a siding square?
100 square feet.
Should windows and doors be deducted?
They can be deducted when their approximate combined area is known.
Does this calculate siding pieces?
No. Product dimensions and packaging vary, so this calculator estimates coverage area.
Using this calculator effectively
The siding calculator estimates exterior wall area from building perimeter and height, subtracts entered openings and converts the adjusted area into siding squares. It is useful for early coverage planning on simple rectangular buildings.
Common uses
- Estimating siding square footage for exterior walls.
- Converting wall area into 100-square-foot siding squares.
- Comparing gross wall area with an opening deduction and waste allowance.
Tips for a better estimate
- Measure gables, dormers and irregular elevations separately.
- Use realistic opening areas instead of automatically deducting every small opening.
- Check the actual product coverage and installation waste before ordering.
Related calculations
Tile Calculator · Flooring Calculator · Square Footage Calculator