Board and batten wall calculator

New to this? Words explained.

How even spacing is calculated

With a batten at each end, a wall of width W holds n battens of width b and n − 1 equal gaps. Solve for the number of battens closest to your target gap, round it, then work back to the exact gap. Covering the wall in horizontal boards instead? The shiplap calculator counts rows and boards.

n = (W + target gap) ÷ (b + target gap), rounded
exact gap = (W − n × b) ÷ (n − 1)
center-to-center = exact gap + b

Example: a 12 ft (144 in) wall with 2½ in battens and a 16 in target: (144 + 16) ÷ 18.5 = 8.6, so 9 battens. Exact gap = (144 − 22.5) ÷ 8 = 15.19 in (about 15-3/16 in).

Common layouts

• Classic vertical accent wall: 1×3 or 1×4 battens, 12–24 in apart, with a top rail and sometimes a shelf ledge.
• Grid or “box” board and batten: add a middle rail and treat it as a separate even division vertically.
• Exterior board and batten siding uses wide boards with narrow battens over the joints — a different layout, and the siding maker’s spacing and fastening rules apply.

Install tips

• Mark stud locations before you start. Nail battens into studs where you can and use construction adhesive between them.
• Cut a spacer block to the exact gap. It is faster and more consistent than measuring each one.
• Check each batten with a level rather than trusting the floor — floors and ceilings are rarely true.
• Primed MDF strips are common for interior walls; solid wood is better where the battens might get wet or knocked.

The same even-division idea works outdoors: a spaced picket fence is battens with the gaps swapped for pickets — see How many pickets for a 100 ft privacy fence. Cutting battens and rails from 8 ft sticks runs into saw kerf the same way shelving does, as How many 24 in pieces from an 8 ft board shows.