Board and Batten Calculator
Lay out equal vertical battens across identical wall sections with a batten at each edge. Calculate by a maximum desired clear gap or by a chosen batten count, then estimate cuts, stock pieces and cost.
Board and batten spacing formulas
Convert batten width and desired gap to the same unit as the wall. When calculating from a maximum gap:
Battens = max[2, ceil((wall width + desired gap) ÷ (batten width + desired gap))]
For either method:
Equal clear gap = (wall width − battens × batten width) ÷ (battens − 1)
Center spacing = clear gap + batten width
Installed battens = battens per wall × identical walls
Order battens = ceil(installed battens × (1 + allowance ÷ 100))
Full battens per stock piece = floor(stock length ÷ batten height)
Stock pieces = ceil(order battens ÷ full battens per stock piece)
Worked examples
| Wall and battens | Layout | Calculated result |
|---|---|---|
| 12 ft wall, 8 ft battens, 1.5 in wide | Maximum 16 in gap; 10% extra; 16 ft stock | 10 battens; 14.333 in gaps; 11 ordered; 6 stock pieces |
| Two 10 ft walls, 9 ft battens, 2 in wide | Maximum 12 in gap; 5% extra; 12 ft stock | 10 per wall; 11.111 in gaps; 21 ordered; 21 stock pieces |
| 15 ft wall, 8 ft battens, 2 in wide | Choose 12 battens; no extra; 16 ft stock | 14.182 in gaps; 12 battens; 6 stock pieces |
| 4 m wall, 2.7 m battens, 4 cm wide | Maximum 50 cm gap; 10% extra; 5.4 m stock | 9 battens; 45.5 cm gaps; 10 ordered; 5 stock pieces |
| Two 6 m walls, 3 m battens, 5 cm wide | Maximum 60 cm gap; 5% extra; 6 m stock | 11 per wall; 54.5 cm gaps; 24 ordered; 12 stock pieces |
| Three 3 m walls, 2.4 m battens, 3 cm wide | Choose 8 per wall; 12.5% extra; 4.8 m stock | 39.429 cm gaps; 27 ordered; 14 stock pieces |
How to plan the layout
- Measure the actual width of one uninterrupted wall section.
- Enter the visible installed width of the battens, not only their nominal product name.
- Choose a maximum desired clear gap or a fixed batten count.
- Confirm that placing battens at both edges matches the intended visual layout.
- Add an allowance for selection, damage and mistakes.
- Enter a stock length that can produce continuous battens of the required height.
- Mark every centerline on the wall and verify the end conditions before cutting.
Important limitations
- The tool assumes one batten at each wall edge and equal clear gaps between battens.
- Doors, windows, corners, outlets and non-identical wall sections require separate layouts.
- The stock calculation only counts full-height cuts; it does not optimize mixed trim or shorter pieces.
- It does not calculate backing panels, full-width boards, horizontal rails, top caps, baseboards, fasteners, adhesive or paint.
- Exterior systems must follow the selected product’s fastening, drainage, flashing, clearance and installation requirements.
- Nominal lumber dimensions may differ from actual visible installed width.
- Cost excludes labor, finishing, waste from defects, delivery and tax.
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Frequently asked questions
How do I calculate equal board and batten spacing?
Enter the wall width, visible batten width and either the maximum desired gap or the number of battens. The calculator returns an equal clear gap and center spacing.
Are battens included at both wall edges?
Yes. Every layout assumes a batten centered at each edge. Use a separate wall section when doors, corners or windows change the layout.
What is the difference between clear gap and center spacing?
The clear gap is the open distance between batten edges. Center spacing equals that gap plus one batten width.
Can I enter a fixed number of battens?
Yes. Choose the count method and enter at least two battens per wall. The tool calculates the resulting equal gap.
Does it calculate full siding panels?
No. Use Siding Calculator for wall area, packages and material cost. This tool focuses on batten layout and full-height stock cuts.
Can I use metric measurements?
Yes. Enter wall and stock lengths in meters and batten width or spacing in centimeters.