Lumber & framing calculator

Linear lumber calculator

Whole stock-board count from total linear run, selected stock length and visible allowance.

Calculator result and formula

Stock boards to order: 11 boards

Formula: Total run × (1 + waste) ÷ stock length → whole boards

Formula ID: LUM-LINEAR-001 · Version 1.0.0 · Published · Last reviewed Aug 26, 2026.

Inputs

  • Total linear run: Sum of trim, fascia, blocking or board runs Default: 120.
  • Stock board length: Length of one purchasable board Default: 12.
  • Waste factor: Allowance for cuts, defects and pattern selection Default: 10.

How this calculator works

This calculator divides a measured total linear run plus allowance by the selected stock-board length and rounds up to whole boards.

  1. Sum all like linear runs that share one stock material.
  2. Enter the purchasable stock length rather than a theoretical cut length.
  3. Use a visible allowance for cuts, defects, pattern matching or splice layout.

Worked example: Example: 120 ft of linear run at 10% allowance requires 132 ft. With 12 ft stock boards, the order rounds to 11 boards.

Assumptions and limitations

  • All runs are assumed to use the same stock material and stock length.
  • Waste is added before whole-board rounding.
  • Detailed cut lists and layout optimisation are excluded.

Common mistakes to avoid

  • Confirm the measurement basis and units before using the result.
  • Keep waste or allowance visible and adjust it for the actual job conditions.
  • Confirm supplier packaging, delivery increments, specifications, and final site requirements before ordering.

Calculator disclaimer

This planning calculator does not determine structural design, code compliance, installation requirements, or guaranteed pricing. Confirm final requirements with the appropriate responsible professional, authority, manufacturer, and supplier.

Formula review and sources

Internal QA complete · independent external review pending · 1 source reference.

Related calculators

Enable JavaScript to use the interactive calculator and save a project estimate.