Calculator / Decision example
Flush end battens or equal edge margins?
Written for this calculation decision · reviewed October 12, 2026 · TwoCut.
Boundary conditions change the number of gaps
For a 96 in wall, 3.5 in actual battens and a maximum 16 in clear gap, flush ends require six battens. The remaining clear width is 96 − 6 × 3.5 = 75 in, divided among five internal gaps: 15 in each. The end boards occupy the boundary; they are not added outside the wall width.
Leaving matching margins is a different layout
With equal clear spaces at both ends, five battens occupy 17.5 in. The remaining 78.5 in is shared by six spaces, giving 13.0833 in per space. The calculator can therefore return one fewer board even though the same maximum gap was entered. Do not reuse the flush-end marking list after changing the edge option.
Mark absolute positions, not repeated rounded steps
The first equal-margin board starts at 13.0833 in. Its neighbors advance by a 16.5833 in pitch. Rounding every gap independently and then adding the rounded values can accumulate error. Measure each left edge from the same wall boundary. A tape mark rounded to the nearest sixteenth is a practical approximation, not the exact mathematical position.
Which option fits the wall?
Flush ends create deliberate edge framing; equal margins suit a floating arrangement or a wall where the edge cannot take a board. Check switches, outlets and adjacent trim before choosing. The Lowe’s accent-wall guide explains excluding board width before dividing the remaining spaces. The count here is independently derived from that geometry, not a manufacturer-approved design. Rails, backing and structural fasteners are outside this spacing estimate.
Compare the purchasing decision
| Alternative | Arithmetic | Buying implication |
|---|---|---|
| Flush ends | 6 battens / 5 spaces | 15 in gap |
| Equal margins | 5 battens / 6 spaces | 13.0833 in gap |
These alternatives use the stated model rather than field measurements. A lower headline quantity is useful only when the product inputs and required cuts are correct.