Solar bill of materials quantity calculator
Enter the array layout, the runs and your allowances. It returns design counts and order quantities for a rail-based roof job.
Quantity take-off only. It does not check spans, voltage, wire size or code. Take rail pieces and attachments per line from your racking calculation, and wire and breaker sizes from your design. The allowances are yours to set; the presets are examples, not industry figures. The tool holds no prices: type your own to see a cost split.
| Item | Unit | Design | Allowance | Order | Unit price (optional) | Cost |
|---|
Order = design count x (1 + allowance), rounded up to a whole unit. Rail pieces, modules and protection devices carry no allowance here. Whole-unit rounding means small counts rise by more than the allowance.