About this calculator
Siding takeoff in squares and boards, with starter strip, J-channel around openings, corner posts and house wrap.
How it’s calculated
Area = wall length × height + gables − openings. Boards = area × (1 + waste) ÷ (exposure × board length). A square is 100 sq ft of wall.
Worked example
With these inputs:
- Wall length to clad
- 160 ft
- Wall height
- 10 ft
- Gable ends
- 2
- Gable width
- 28 ft
- Gable height
- 7 ft
- Openings area
- 120 sq ft
- Number of openings (doors + windows)
- 10
- Outside corners
- 4
- Board exposure / cover width
- 7 in
- Board length
- 12 ft
- Waste allowance
- 10%
the result is:
- Boards needed
- 264 boards
- Net wall area
- 1,676 sq ft
- Squares (100 sq ft)
- 18.44
Tips from the trade
- Use the exposed face (exposure or cover width), not the full board width.
- Ventilate behind the cladding at the top and bottom of the cavity.
Results are estimates for planning and pricing. Check quantities against your drawings, the manufacturer’s data and local building codes before ordering.