Siding waste factor by house layout
Typical published planning values — NOT a certified spec or professional advice. Coverage and exposure vary by product and installation; confirm on the manufacturer’s installation instructions and stated coverage. Moisture, flashing, sheathing and pre-1978 lead paint on old siding are a pro’s call — follow the manufacturer’s instructions, local code and the EPA RRP rule and hire a certified firm; lead-paint abatement, structural and moisture repairs and code certification are not engineered here.
This companion table gives the LABELED waste factor by house layout — the other half of the how-much-siding identity. Waste covers cuts, corners, gables and mistakes: use ~10% for a simple rectangle, 12–15% for a complex layout, and 15%+ for cedar shakes or a diagonal pattern — what the waste factor actually pays for, and what pushes a house from 10% to 15%, is worked through with an example in the guide. Confirm against your own layout. It backs the how-much-siding calculator and the waste-factor calculator.
| House layout | Waste factor |
|---|---|
| Simple rectangle, few openings | ~10% |
| Average house, some gables & corners | 10–12% |
| Complex — many corners, gables, dormers | 12–15% |
| Cedar shakes / shingles / diagonal pattern | 15%+ |
LABELED planning snapshot — measure your actual layout. Many corners, gables and dormers, and cedar shakes or a diagonal pattern, all use more material; round up to whole squares/boxes/bundles. Snapshot: 2026-07-13.