Board & Batten Spacing Calculator
Lay out battens evenly across a wall. Enter the wall width, the batten width, and either a target panel width or a set number of panels — and get the exact panel size, the batten count, the edge gaps, and a centerline for every batten to mark.
Work in inches — a 10 ft wall is 120 in. A "1×4" batten is 3.5 in wide.
The calculator picks the whole number of panels closest to this.
The gaps between (and beside) battens.
Formula & how it works
With a batten in each corner and P panels, there are P + 1 battens and panel = (wall − (P+1) × batten) ÷ P. From a target, P = (wall − batten) ÷ (target + batten), rounded to a whole number.
Batten centers step by panel + batten. With corner battens the first center sits half a batten in from the edge; with panels at the ends, the first gap equals a full panel.
Worked example
A 120 in wall with 3.5 in battens and a 16 in target, battens in the corners: (120 − 3.5) ÷ (16 + 3.5) ≈ 6 panels, so 7 battens and an exact panel of 15.92 in. Centers land at 1.75, 21.17, 40.58, 60, 79.42, 98.83, and 118.25 in — symmetric around the wall's middle. Switch to panels-at-the-ends and you get 5 battens with a 17.08 in gap at each corner.
Laying out battens that look right
Equal panels are what the eye reads
The whole point of the layout is that every panel between battens is identical — an uneven last panel is the giveaway of a rushed job. Rather than guessing a spacing and hoping it divides evenly, pick the panel width you want and let the count round to the nearest whole number, which shifts the exact panel only slightly while keeping every gap equal.
Decide the corners first
Whether a batten lands in each corner or a panel runs to the edge changes the count and the whole feel of the wall. Corner battens frame the composition and are the common choice; panels at the ends give a lighter, more open look. Set the end condition before anything else, because it determines how many battens you're buying.
Mark centers, dry-fit, then nail
Work from the centerlines this tool lists, measuring each from the same left edge so errors don't accumulate. Real walls are rarely dead plumb and outlets or window trim can interrupt a batten, so hold the pieces up and dry-fit the layout before committing. A laser or a long level makes marking the verticals far faster than a tape alone.