Productivity Calculator

DIY & wall projects

Board and Batten Calculator

Plan evenly spaced battens before you cut. Get the clear gap, a wall preview, marking positions, and a cut list for one rectangular interior feature wall.

Inches & millimetersFraction inputsCompare layoutsPrint your plan

Your wall, your layout

One batten sits flush at each side. Both end battens are included in the total.

Need help measuring? Follow our illustrated wall measuring guide, with rail diagrams and a printable worksheet.

Use measured widths, not lumber names. Decimals or fractions work: 3.5, 3 1/2, or 1/2. Convert feet to total inches first.

Between 2 and 200 battens per wall.
Height & horizontal rails
Includes the rails selected below. Vertical battens fit between full-width rails.
Adds to length estimates, not individual cut sizes.

Your layout plan

Select your measurements and calculate a layout.

Before you start

How to measure your wall

  1. Choose the finished area. Measure the full width where the two end battens will sit and the overall height, including selected rails.
  2. Measure the actual timber. Enter the visible face width of a batten. A product name may not match its measured dimensions.
  3. Choose a count or a gap. The count includes both end battens. A clear gap is the empty space between boards, not the distance between their centers.
  4. Check the wall in several places. Dry-fit battens and check outlets, switches, corners, and trim before making cuts.

Know what is included

A plan for one interior wall

This tool uses equal-width vertical battens with a batten at each end. Horizontal rails span the entire width; the vertical pieces fit between them.

For an existing baseboard, include its face height as the bottom rail and omit that piece from your shopping list, or measure from above it and turn the bottom rail off.

Windows, doors, sockets, sloped walls, corner joints, and exterior siding overlaps are not automatically accounted for. Plan uninterrupted sections separately and check how they meet.

The drawing shows geometry, not a fastening or structural specification.

The calculation, explained

Board and batten spacing formula

Let W be wall width, B actual batten width, and N the total batten count including both ends. There are N − 1 equal spaces.

Clear gap = (W − N × B) ÷ (N − 1)
Center-to-center spacing = clear gap + B
Batten k left edge = (k − 1) × (clear gap + B)

For a target gap, the tool checks feasible counts from 2 to 200 and selects the count whose clear gap is closest to your target. An exact tie favors fewer battens. The target is a preference, not a maximum allowed gap.

Worked example: a 120-inch wall

Six 3.5-inch battens occupy 21 inches. The remaining 99 inches divide into five spaces: a 19.8-inch clear gap and 23.3-inch center-to-center spacing.

The left edges are 0, 23.3, 46.6, 69.9, 93.2, and 116.5 inches. The last batten ends at 120 inches. With a 48-inch overall height and two 3.5-inch rails, each vertical cut is 41 inches.

Rounding and material allowance

Calculations retain precision internally. Decimal results show up to three places; inch tape marks round each absolute position to the nearest 1/16 inch. Repeating a rounded gap can accumulate error, so use absolute positions.

Allowance increases estimated material lengths only. Six 41-inch cuts need 246 inches before allowance, or 270.6 inches with 10% extra. This does not establish how many stock boards to buy.

Board and batten layout questions

Does the batten count include both ends?

Yes. Six battens means two end battens and four between them, with five clear spaces. A full-width batten sits at each edge.

Should I enter the gap or center-to-center spacing?

In target-gap mode, enter the empty space between neighboring board edges. To convert a desired center-to-center distance, subtract one actual batten width.

Can I enter fractions or switch to millimeters?

Yes: 3.5, 3 1/2, and 1/2 are accepted. Changing units converts the entered dimensions using 25.4 millimeters per inch. Convert feet to total inches first: 10 feet equals 120 inches.

What if I do not know how many battens look best?

Choose a target gap, calculate, and compare the neighboring counts. More battens make narrower gaps; fewer make wider gaps. Try masking tape on the wall to judge proportions.

Does this account for windows or exterior siding?

No. This is for one uninterrupted rectangular interior wall. Openings need separate measurements. Exterior siding requires weatherproofing, overlaps, and product-specific installation details beyond this tool.

Can I save the layout?

Use Print / Save PDF after calculating. The print view includes dimensions, a wall drawing, the cut list, and marking positions. Choose Save as PDF in the browser print dialog if available.

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