What a board and batten calculator does
A board and batten calculator tells you where to put each batten so the gaps on your wall are equal. You give it the wall width, the width of your battens and how many you want. It returns the exact gap, a pencil mark for the center of every batten, and the boards to buy. This board and batten spacing calculator also draws the wall to scale, so you can see the result before you cut anything.
Equal gaps matter because the eye catches a small difference. If six gaps are 12 inches and the last one is 9, the wall looks wrong, even when no one can say why.
How to space board and batten on a wall
- Measure the wall width in two or three places. Use the smallest number.
- Choose your batten width. A 1x2 is 1 1/2 inches wide, a 1x3 is 2 1/2 and a 1x4 is 3 1/2. These are the real sizes, not the names on the label.
- Pick the number of battens, or type the gap you like and let the tool choose the count.
- Decide if you want a batten at each end of the wall. Most people do, because the end batten hides the joint at the corner.
- Copy the marks. Measure from the left edge of the wall and mark the center of each batten at the listed distance.
The formula
With a batten at each end, the number of gaps is one less than the number of battens:
gap = (wall width − battens × batten width) ÷ (battens − 1)
With a gap at each end instead, add one:
gap = (wall width − battens × batten width) ÷ (battens + 1)
The distance from one batten center to the next is the batten width plus the gap. Builders call this the on-center spacing.
Worked example: a 12 foot wall
The wall is 144 inches wide. You use 1x3 battens, 2 1/2 inches wide, and want 10 battens with one at each end.
Ten battens take 25 inches. That leaves 119 inches for 9 gaps. Each gap is 13.22 inches, which is 13 1/4 inches on a tape measure. The on-center spacing is 15 3/4 inches.
The first center mark is 1 1/4 inches from the left edge. The last one is 11 feet 10 3/4 inches. The tool rounds each mark to the nearest 1/16 inch, so no mark is off by more than 1/32 inch.
Common wall sizes with 1x3 battens
These values use 2 1/2 inch battens, with a batten at each end. Each count gives the gap nearest 12 inches or 16 inches.
| Wall width | Battens | Gap | Battens | Gap |
|---|---|---|---|---|
| About 12 in gap | About 16 in gap | |||
| 8 ft | 7 | 13 1/16" | 6 | 16 3/16" |
| 10 ft | 9 | 12 3/16" | 7 | 17 1/16" |
| 12 ft | 11 | 11 5/8" | 9 | 15 3/16" |
| 14 ft | 12 | 12 9/16" | 10 | 15 7/8" |
| 16 ft | 14 | 12 1/16" | 11 | 16 7/16" |
How wide should the gaps be?
Most board and batten walls use gaps of 8 to 16 inches. Narrow gaps look formal and busy. Wide gaps look modern and calm. A common starting point is 12 inches. Try a few counts with the tool and compare the drawings. The one that feels right on screen will feel right on the wall.
The wall height and the room matter too. A tall hallway can take wider gaps than a small powder room. Many people also line up the battens with a window or a door. If you want that, mark the window edges first and test the count that puts a batten there.
Horizontal rails and the boards to buy
If your design has a top rail, turn on the rails option. The tool spaces them from the floor to the ceiling and adds them to the cut list. Rails are longer than most boards, so the tool splits them and counts the pieces.
The boards table shows how many 8, 10 and 12 foot boards you need. It allows 1/8 inch for each saw cut and packs the pieces to waste as little as possible. The best option is highlighted. Buy one extra board, because a bad cut or a bowed board happens.
Planning a whole room
Measure each wall on its own. Run the numbers for each one and keep the same gap on every wall, so the room looks even. Start from a corner and work around. If a wall has a window, a door or an outlet, mark those first and check that no batten lands on an edge.
Tips before you nail
- Draw a level line across the wall for the top rail first. Then mark the batten centers along it.
- Use a plumb line or a laser for each batten. Walls and ceilings are rarely square.
- Find the studs. Nail the battens into studs where you can, and use construction adhesive between them.
- Cut the battens after you finish the first one, and check the next against it.
- Caulk the seams and fill the nail holes before you paint.