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Board and batten calculator

To space battens evenly, place one at each end of the wall and divide the remaining width by the number of gaps: (wall width − number of battens × batten width) ÷ (battens − 1). Enter your wall and the gap you are aiming for, and the calculator finds the closest even layout.

Target gap is the space you'd like between battens; the calculator evens it out. A 1 × 3 is 2 1/2 inches wide and a 1 × 4 is 3 1/2 inches. Rails run the full width, for a grid or a wainscot top rail.

Board length and price
15.2 in gap12 ft wall, 9 battens
Batten layoutBattens at both ends
Vertical battens9
Exact gap between battens15.19 in
Center to center17.69 in
Total linear feet72.0 ft
Boards, 8 ft long9
Boards are counted per piece, so offcuts are not reused across battens.

How to calculate board and batten spacing

  1. Measure the wall width in inches.
  2. Choose a target gap, for example 16 inches.
  3. Estimate the number of battens: (wall width − batten width) ÷ (gap + batten width), rounded, plus 1.
  4. Find the exact gap: (wall width − battens × batten width) ÷ (battens − 1).
  5. Mark the wall at the center-to-center spacing, starting from one end.

Worked example. A wall 10 ft 6 in wide (126 inches) and 4 ft high, with 3 1/2 inch battens and a target gap of 12 inches: (126 − 3.5) ÷ 15.5 = 7.9, so 8 + 1 = 9 battens. The exact gap is (126 − 31.5) ÷ 8 = 11.81 inches, or 11 13/16. Nine 4 ft battens plus one 10 ft 6 in top rail come to 46.5 linear feet: 5 boards for the battens (two per 8 ft board) and 2 for the rail.

Batten sizes

Lumber is sold by nominal size, but the actual board is smaller. Enter the actual width.

NominalActual width
1 × 21 1/2 in
1 × 32 1/2 in
1 × 43 1/2 in
1 × 65 1/2 in
1 × 87 1/4 in

All are 3/4 inch thick. Thin MDF or plywood strips are also common for interior accent walls; measure the ones you buy.

Layout tips

  • Install the top rail or baseboard first, then fit vertical battens between them.
  • Check each batten with a level; walls and floors are rarely square.
  • Around outlets and windows, shift the layout so cuts land in a gap, then recalculate the spacing for that section.
  • Buy one or two spare boards for bad pieces and miscuts.

For trim, baseboard or other lengths, total them with the linear feet calculator. On a gable wall, the roof slope calculator gives the angle for cutting battens under the roof line; common angles are in the roof pitch chart.

Questions about board and batten

How far apart should board and batten be?

There is no fixed rule; it is a design choice. Gaps around 12 inches give a busier, more detailed look, while 20 to 24 inches looks calmer on long or tall walls. Pick a target and let the calculator even it out.

How do I space battens evenly?

Put a batten at each end, then divide what is left of the wall by the number of gaps: (wall width − battens × batten width) ÷ (battens − 1).

What size boards are used for board and batten?

Accent walls often use 1 × 3 or 1 × 4 battens (2 1/2 or 3 1/2 inches wide). Exterior siding often pairs wide boards such as 1 × 8 or 1 × 10 with 1 × 3 battens over the joints.

Should the gap be measured edge to edge or center to center?

Either works if you are consistent. The calculator gives both: the gap between battens and the center-to-center spacing for marking the wall.

By the SiteFigure team. Updated . Spacing is a design choice; these figures show the math, not a rule.

Sources

Last reviewed November 9, 2026. Found a wrong figure? Tell us.