# Shiplap Calculator

Calculate how many shiplap boards you need for your wall project. Enter wall dimensions and board specs to get board count, linear feet, and coverage area.

## What this calculates

Shiplap is one of the most popular wall treatments for adding character to any room. This calculator helps you determine exactly how many boards you need based on your wall dimensions, board width, and overlap amount, so you can order the right quantity and avoid multiple trips to the lumber yard.

## Inputs

- **Wall Width** (ft) — min 1, max 100 — Width of the wall to cover
- **Wall Height** (ft) — min 1, max 30 — Height of the wall to cover
- **Board Width** (in) — min 3, max 12 — Nominal width of each shiplap board
- **Overlap** (in) — min 0, max 2 — How much each board overlaps the one below (typically 0.5" to 1")
- **Board Length** (ft) — min 4, max 16 — Length of shiplap boards you plan to buy
- **Openings to Subtract** — min 0, max 20 — Number of doors/windows (assumes ~15 sq ft / 1.4 m² each)

## Outputs

- **Rows of Boards** — Number of horizontal rows to cover the wall height
- **Boards Needed** — Total boards required (before waste)
- **Total Linear Feet** (ft) — Total linear footage of shiplap needed
- **Area Covered** (sq ft) — Net wall area to be covered
- **Boards (with 10% waste)** — Boards to purchase including waste for cuts and errors

## Details

Shiplap boards overlap each other, meaning the effective coverage width is less than the nominal board width. A 6-inch board with a 3/4-inch overlap covers only 5.25 inches per row. The calculator divides the wall height by this effective width to determine the number of rows needed.

Standard shiplap boards come in 6-inch and 8-inch widths, with lengths of 8, 12, or 16 feet. Wider boards cover walls faster but produce more waste on cuts. For walls wider than your board length, you will need to stagger joints between rows for a professional appearance.

Always purchase 10% extra to account for end cuts, waste from working around outlets and corners, and the occasional warped board. For accent walls with many angles or irregular shapes, consider 15% waste. Pine shiplap typically costs $1.50-$4 per linear foot, while cedar runs $3-$8 per linear foot.

## Frequently Asked Questions

**Q: How do I calculate shiplap for a wall?**

A: Measure the wall width and height. Subtract the overlap from the board width to get the effective coverage width. Divide the wall height by the effective width to get the number of rows. Multiply rows by the number of boards per row (wall width divided by board length). Add 10% for waste.

**Q: What is the difference between shiplap and tongue and groove?**

A: Shiplap boards have a rabbet (notch) cut into the top and bottom edges that overlap when installed. Tongue and groove boards have a protruding tongue on one edge that fits into a groove on the adjacent board. Both create a similar look, but shiplap is typically easier to install and more forgiving of imperfect walls.

**Q: Should shiplap be installed horizontally or vertically?**

A: Horizontal installation is traditional and the most common. Vertical installation creates a more modern look and can make ceilings appear higher. The calculation method is the same for both orientations; just swap which dimension determines rows versus board cuts.

**Q: How much does shiplap cost per square foot?**

A: Pine shiplap costs $1.50-$4 per linear foot ($3-$8 per square foot installed). Cedar shiplap runs $3-$8 per linear foot ($6-$14 per square foot installed). MDF shiplap is the most economical at $1-$2 per linear foot. Installation labor adds $2-$5 per square foot if hiring a professional.

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Source: https://vastcalc.com/calculators/construction/shiplap
Category: Construction
Last updated: 2026-04-21