Introduction
Board and batten siding looks best when the boards are spaced evenly. This board and batten calculator does that math for you. Type in your wall width, batten width, and wall height, and it tells you how many battens you need and how far apart to put them.
You can work three ways. Pick a spacing you like and get the batten count. Pick a batten count and get the exact spacing. Or pick how many open panels you want and get both. You can also choose whether the battens sit flush at the wall corners or leave an equal gap at each end.
The results include the exact gap size in inches, feet, centimeters, or meters, plus tape measure fractions down to 1/32 of an inch. You also get a scaled wall drawing, a list showing where each batten goes measured from the left edge, and the full math laid out step by step. Use it to plan siding, accent walls, or interior trim before you cut a single board.
How to use our Board and Batten Calculator
Enter your wall size, your batten size, and one spacing choice. The calculator gives you the batten count, the panel count, the exact gap, the edge gap, and the total board length you need, plus a layout diagram and a list of positions to mark on the wall.
Wall Width: Type the full width of the wall you want to cover. Pick inches, feet, centimeters, or meters from the drop-down next to the box.
Batten Width: Type the real width of one board. A 1×4 board is 3.5 inches wide, not 4 inches. Pick the unit next to the box.
Wall Height: Type how tall the battens will run. This is used to work out the total board length you must buy.
Layout Style: Choose "Equal gaps everywhere" if you want the same gap at both corners and between every board. Choose "Battens flush at both wall corners" if you want a board to sit right at each end of the wall.
Calculation Mode: Click one of the three tabs to pick what you know. Tab 1 works out the batten count, tab 2 works out the spacing from a batten count, and tab 3 works out the spacing from a panel count.
Desired Spacing (Tab 1): Type the gap you want between boards. The calculator rounds to the closest layout that fits the wall evenly.
Number of Battens (Tab 2): Type how many boards you want on the wall. Use a whole number.
Number of Panels (Tab 3): Type how many open spaces you want between the boards. Use a whole number.
Display Results In: Pick inches, feet, centimeters, or meters for your answers. You still get inch fractions for your tape measure.
Round Fractions To Nearest: Pick 1/8, 1/16, or 1/32 inch. This sets how fine the tape measure marks are.
Calculate and Reset: Results update as you type, but you can click Calculate to refresh them. Click Reset to go back to the default board and batten values.
What Is Board and Batten Siding?
Board and batten is a wall style made of two parts. The flat back layer is the board (or panel). The narrow strips nailed on top are the battens. The battens run up and down, and the open spaces between them are called panels. People use this look on outside siding, barns, accent walls, and bathroom walls. Inside the house, many people build the back layer from sheet goods sized with a drywall calculator.
Batten Spacing
Spacing is the open gap between two battens. Most walls look best with gaps of about 8 to 16 inches. Wide gaps feel calm and modern. Narrow gaps look busy and more like an old farmhouse. The key rule is that every gap should be the same size, so the wall looks even from end to end.
Common Batten Sizes
Lumber is sold by nominal size, but the real size is smaller. A 1×2 is about 1.5 inches wide. A 1×3 is about 2.5 inches. A 1×4 is about 3.5 inches. A 1×6 is about 5.5 inches. Always use the real width when you plan a layout, or your spacing will be off.
Two Ways to Lay Out Battens
Equal gaps everywhere: the wall starts and ends with a gap, so battens sit a little in from each corner. The number of gaps is one more than the number of battens.
Battens flush at the corners: a batten sits right at each end of the wall. This hides the corner joints and frames the wall, but you get one fewer gap than the number of battens.
Simple Math Behind It
The wall width is used up by the battens plus the gaps. If W is wall width, w is batten width, n is the number of battens, and g is the gap:
- Equal gaps: W = n × w + (n + 1) × g
- Battens at corners: W = n × w + (n − 1) × g
You almost never get a round number gap. Pick your batten count first, then let the math give you the exact gap, even if it lands on something like 12 7⁄16 inches.
Install Tips
Mark each batten from one end of the wall, not from the last batten. Small errors add up fast if you measure batten to batten. Snap plumb lines with a level or laser before you nail. Nail battens into studs or into the board layer with construction glue plus finish nails. A stud calculator shows where the framing members land. Caulk and paint the seams so water cannot get behind the wood on outside walls.