117 Industrial Drive

Momence, IL 60954


Coverage Calculations

Siding and paneling are usually sold by the lineal (running) foot or by the board foot.

To simplify cost and coverage estimations, select the appropriate factor from the table according to how the material is priced. The factors provided in the table can be used to calculate the amount of siding required either in lineal feet or in board feet.

In either case, the square footage of the area to be covered is calculated first, then multiplied by the appropriate factor.


  1. Calculate the square footage in walls: length x width = sq. ft.
  2. Calculate, and then subtract, the square footage of openings. Add 10% for trim and waste.
  3. Multiply the result by either the factor for lineal feet or the factor for board feet.
  4. Multiply the total footage required by price.

Lineal Foot Factor is derived by dividing 12” by the exposed face width.

Board Foot Factor is derived by dividing the nominal width by the exposed face width and is based on nominal 1” stock, except log cabin.
Log cabin is based on 2” thickness. For nominal 1 1/2” log cabin, multiply by .75.

Note: Factors do not include any allowance for trim or waste and do not apply to diagonal installations. A 10% allowance (for trim and waste) should be added to the square footage required before the factors are used. Refer to Procedure above.

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