Siding Estimator
Vinyl siding squares, boxes, starter strip, J-channel, and corner posts from your wall perimeter, height, and openings — with waste built in.
FAQ
- How much vinyl siding do I need?
- Multiply the wall perimeter by the height for gross area, subtract standard door (21 ft²) and window (15 ft²) openings, add 10% waste, then divide by 100 for squares. One box covers about 2 squares (200 ft²).
- What is a square of siding?
- One square equals 100 square feet of wall coverage. Vinyl siding is sold by the box, and a typical box covers about two squares — confirm the exact coverage on the product label.
- What accessories do I need besides panels?
- Starter strip runs the full bottom perimeter, J-channel frames every door and window opening, and corner posts run the full wall height at each inside and outside corner. This calculator estimates the linear feet and pieces for each.
Rooms you can plan with this tool
Real-room inspiration that uses this tool's outputs.