What the calculator estimates
The calculator converts surface dimensions into net square footage, then divides by exposed face to estimate board count and linear feet before applying waste.
Plan shiplap before you buy boards
Enter wall or ceiling dimensions, choose a board size, and compare board counts with linear feet. Coverage changes with overlap and board profile, so use this as a planning estimate and confirm with your supplier.
SurfaceAccent wall
Board profileNickel gap
Waste factor10%
Surface dimensions
For rooms with several walls, add each wall separately or combine the total length.
Board and cost
Exposure is the visible face after overlap. A nickel-gap profile hides roughly 1/8 inch between boards.
Common board sizes
1x6 shiplap shows roughly 5 inches exposed, 1x8 shows about 7 inches, and nickel-gap planks often show 5.5 inches. Always confirm the true exposure for your product.
Planning note
Real coverage changes with board profile, overlap, stud spacing, corners, and installer. Confirm board exposure, lengths, and bundle quantities with your supplier.
Formula used
- Convert length and height to feet.
- Gross square feet = length x height.
- Net square feet = gross minus opening deductions.
- Exposure in feet = exposed face / 12.
- Rows = height / exposure, rounded up.
- Boards per row = length / board length, rounded up.
- Linear feet = rows x length (net), including waste factor.
How much shiplap do I need for an accent wall?
Multiply wall length by height for square footage, then divide by the board's exposed face in feet. Add a 10 to 15 percent waste factor for cuts, corners, and offcuts. This calculator automates that math for any board width.
What is the difference between shiplap and nickel gap?
Shiplap boards overlap directly with an rabbet cut, while nickel-gap planks use a spacer to leave a consistent 1/8 inch reveal between boards. Both are installed horizontally and estimated the same way by exposed face.
Should I subtract windows and doors?
Yes. Subtract the area of openings to avoid over-ordering, but keep some waste factor because boards still need to be cut and fitted around frames. Enter the number of openings and an average size to deduct them here.
How much waste should I add for shiplap?
A 10 percent waste factor is common for straight rectangular walls. Use 15 to 20 percent for walls with many corners, outlets, or angled ceilings, and for shorter board lengths that create more offcuts.
Can I use this for a ceiling?
Yes. Treat the ceiling like a wall using room length and width. Ceilings often need more fasteners and may need furring strips, which this estimator does not include in the cost.
Is this a contractor quote?
No. It is a planning estimate. Prices, fasteners, trim, finish, adhesives, delivery, taxes, and labor vary by supplier, product, and location.