Board and Batten Calculator
Plan board and batten siding. Enter total wall length and wall height in feet and pick a batten spacing (12, 16, or 24 in on center) to get battens, linear feet of batten stock, and 4x8 panel siding sheets with waste.
Example: with Total wall length (ft) 40 · Wall height (ft) 9 · Batten spacing (on center) 16 in OC (most common) · Waste factor (%) 10 → Battens: 31 battens (9 ft each).
- Batten stock279 linear ft of batten stock
- Panel siding13 sheets of 4x8 panel siding (10% waste)
- Wall area360 sq ft of wall
Computed by the calculator below using its default values. Change any input to see your own numbers.
Battens = wall length ÷ spacing + 1 (one closes each run). Sheets assume 4x8 panel siding at 32 sq ft each under the battens.
How modern board and batten is built
Traditional board and batten was wide vertical boards with narrow battens sealing the joints. The common modern version flips the economics: 4x8 sheets of panel siding (T1-11, smart-panel, or fiber cement) go up first, then battens — usually 1x3 or 1x4 — are applied on a regular grid for the look. This calculator covers that build: battens at your chosen spacing plus sheets to cover the wall area.
Batten count per run is length ÷ spacing plus one, because a batten must close each end (and cover each sheet seam). At 16 in OC the battens also land on studs, which makes nailing solid — one reason 16 in is the default.
Choosing spacing and adding trim
Spacing sets the character: 12 in OC reads busy and traditional, 16 in is the safe modern farmhouse rhythm, and 24 in goes wide and contemporary. Whatever you pick, plan extra battens for outside corners (two each), window and door surrounds, and any horizontal belly band — those trim pieces come out of the same stock but are not in the grid count. Ten percent waste on the sheets covers window cutouts and the offcut when wall height passes 8 ft.
How it’s calculated
Battens = floor(wall length × 12 ÷ spacing) + 1, each cut at wall height; batten stock = battens × height in linear feet. Wall area = length × height; sheets = area × (1 + waste%/100) ÷ 32 sq ft per 4x8 sheet, rounded up. Openings are not subtracted — they offset cut waste.
Assumes continuous walls with battens on a uniform grid; gables, corners, and opening surrounds add trim stock beyond the grid count.
Batten spacing on a 40 ft wall
| Spacing | Battens | Look |
|---|---|---|
| 12 in OC | 41 | Busy, traditional |
| 16 in OC | 31 | Classic farmhouse; lands on studs |
| 24 in OC | 21 | Wide, modern |
Computed with battens = length ÷ spacing + 1 for a 40 ft run.
Common mistakes
- Ordering battens for the grid only — outside corners, gables, and window surrounds routinely add 15-20% more batten stock.
- Spacing battens off sheet seams: seams must land under a batten, so set spacing to divide evenly into 48 in (12, 16, or 24), not arbitrary numbers.
- Forgetting walls taller than 8 ft need either 4x9/4x10 sheets or a horizontal band detail at the seam.
- Counting gable walls as rectangles; measure the triangle separately and add its area and progressively shorter battens.
Frequently asked questions
How do I calculate battens for board and batten siding?
Battens per wall = wall length in inches ÷ batten spacing, rounded down, + 1. A 40 ft wall at 16 in on center needs 31 battens, each the height of the wall.
What spacing is standard for battens?
16 in on center is the most common — it matches stud layout and 4 ft sheet widths so seams always land under a batten. 12 in looks more traditional, 24 in more modern.
What size boards are used for battens?
1x3 (2.5 in actual) and 1x4 (3.5 in actual) are the usual battens over panel siding. True board-and-batten uses 1x10 or 1x12 boards with 1x2 or 1x3 battens over each joint.
How many sheets of siding do I need under the battens?
Wall area ÷ 32 sq ft per 4x8 sheet, plus waste. A 40 x 9 ft wall is 360 sq ft — with 10% waste that is 13 sheets.
Do I subtract windows and doors?
Usually no — the openings roughly pay for the cut waste around them. Subtract only large openings like garage doors, and keep the 10% waste on the remainder.