Shiplap Calculator

The calculation engine starts by finding the total surface area of your project using the wall length and height. If your room features doors or windows, their individual areas are subtracted to reveal the net project area. Next, the tool calculates individual shiplap board surface areas (converting dimensions into square inches or feet) to determine how many total planks are needed. Finally, it factors in a user-defined wastage percentage (typically 10% to 15%) and multiplies the final board count and square footage by your material and labor rates to project total expenses.

Imagine you want to install horizontal shiplap on a feature wall that measures 15 feet long by 9 feet high, giving a simple gross area of 135 square feet. The wall includes one standard door measuring 3 feet by 7 feet (21 square feet), making your net complex project area 114 square feet. Suppose your shiplap boards measure 6 inches wide by 8 feet long (4 square feet per board). Dividing 114 square feet by 4 yields 28.5, which rounds up to 29 boards. Adding a standard 10% wastage buffer brings your total board requirement to 32 planks. At $3.50 per board and a labor installation cost of $2.00 per square foot ($228 total labor), your combined material and installation expenses are computed precisely.

Always incorporate a 10% to 15% wastage factor into your calculator inputs to account for end cuts, mistakes, and boards with unusable knots or warping. Before starting construction, let your shiplap planks acclimate in the target room for at least 48 to 72 hours to prevent unwanted expansion or contraction after fastening. Finally, plan your layout carefully from the center of the wall outward to avoid ending up with awkwardly thin strips of wood at the ceiling or floor lines.