Measurement basis
Converting square feet to linear feet requires the effective coverage width of the product. This calculator deducts any overlap or hidden portion from the actual face width, then converts the entered area to a total run length. It adds an optional allowance and rounds to stock pieces. The estimate is useful for siding strips, paneling, narrow boards, and other constant-width products. It does not arrange individual pieces around openings or follow a seam pattern. If the supplier already states an installed coverage width, enter that width directly and set the overlap deduction to zero.
Geometry, units and worked example
A worked example
200 sq ft covered by a 6 in board with 0.5 in overlap needs 436.364 net linear ft. With 10% allowance, that is 480 ft or forty 12 ft pieces.
Enter consistent dimensions
- Confirm whether the product width is actual face width or installed coverage width.
- Subtract overlap only if it is not already reflected in the width.
- Convert area to length, add allowance, and verify how individual cuts fit the stock.
Where the model stops
- Do not subtract tongue-and-groove overlap twice when the manufacturer already gives net installed coverage.
- Different board widths require separate area allocations; a single average can hide layout losses.
- Whole stock rounding is based on combined length, not a mixed-length cutting optimization.
Frequently asked questions
How many linear feet cover 100 square feet?
That depends on coverage width. At 6 inches of effective coverage, 100 square feet needs 200 linear feet.
Should I use nominal or effective board width?
Use effective coverage width for conversion. If entering actual face width, deduct the part hidden by overlap.
Does a gap count as coverage?
A deliberate open gap changes the layout pitch, but it is not covered material. Use a layout-specific tool when gaps are part of the design.
Read the project guides
- Board Feet vs Linear Feet: How to Read a Lumber Quote
Understand board-foot volume, linear-foot length, actual lumber dimensions, effective coverage, and what each price unit means for a project.
Calculation method: JICWH methodology. Examples are planning assumptions, not product recommendations.