Net wall, then gables
Measure wall length times height. Windows you will not side should come out. Gables are triangles — a rectangle overstates the peak.
Lap siding exposure is the face you will see, not the board width. Enter the exposure you will nail.
Wrap is not siding
House wrap, foam and rain-screen furring are companion takeoffs. A square count is not a full rainscreen kit. Inside corners, starter and J-channel stay extras.
Do it in order
- Enter net wall after openings, then gable triangles.
- Type the exposure you will nail, not the board width.
- Apply cut waste, then add wrap, foam and trim as extras.
Worked example — 40 ft × 9 ft wall, two 15 ft² windows, 10% waste
Gross 360 ft² minus 30 ft² openings is 330 ft². With 10% waste that is 363 ft², which is 3.63 squares before gables. Add the triangles separately.
Planning boundary
This is a coverage method. It does not design a rainscreen, a wind rating or a live siding price.
Is board-and-batten the same?
No. That tool counts boards and battens from an exposed module, not squares.
Do I include soffit?
Soffit is a different calculator.
Is this a rainscreen design?
No. Drainage, furring and wrap stay with the responsible professional.