Start with the installed module, not the name on the box
A herringbone floor is a weave of identical rectangles meeting at 90 degrees. Any true rectangle can form the geometric weave: its length does not need to be a whole multiple of its width. What must stay exact is the repeat built from the measured long and short modules. The planner constructs that repeat directly instead of forcing the product onto a square grid.
For tile, each installed module is the measured face plus the intended joint. The example face is 597 × 117 mm with a 3 mm joint, so its placement pitches are 600 × 120 mm. A literal 600 × 120 mm face with the same joint produces different 603 × 123 mm pitches; it is still valid herringbone, but every working line and perimeter mark moves. That is why “3 × 6 tile” is not enough information for a cutting plan.
Use zero for the joint when boards butt together. Measure the covering face, not a tongue that disappears inside the next board. Click herringbone often has handed A and B planks; the drawing uses A and B only for its perpendicular directions. Your carton decides which locking profile occupies each direction.
What the optimiser moves
Manufacturers commonly begin from the room centre and strike working lines for the first A/B pair. Centre is a repeatable starting point, but it does not know where the room walls intersect the pattern. A perfectly centred spine can send a diagonal joint through a corner and leave a tiny triangle at both sides. The planner generates the complete measured field, clips it to the usable rectangle, and searches one full repeat in both set-out axes. It maximises the smallest retained perimeter span, then prefers fewer cut pieces and less fresh stock.
The result keeps the centred value beside the chosen value. That comparison matters. “Optimised” without a before-and-after number is a black box; a shift of 20 mm may be worthwhile when it turns a fragile tip into a usable cut, and irrelevant when both starts already clear the product limit. Strike the dashed spine at the distance shown from the left wall, then transfer the phase crosshair from the top wall. Dry-lay the first A/B pairs on those marks before spreading adhesive or locking a full run.
Single and double are different solved layouts
Single herringbone uses one piece in each arm of the repeating elbow. Double herringbone places two parallel pieces before the direction turns. Both work with rectangular stock, but double makes a wider bundle and therefore uses different translation lines, wall intersections and grouped cuts.
The comparison below the plan is solved, not guessed. It names the other pattern's smallest perimeter piece, fresh-stock count and boxes for the same room and product. Pattern choice can change the order even when the room area is identical, so make it before buying rather than treating double herringbone as a styling toggle after the boxes arrive.
Read a cut as a marking job
A diagonal piece described as “60 × 60 mm” is only a bounding box in the room's axes. Those dimensions may appear nowhere on the stock piece. Every Cutfall cut is first mapped back into its own unrotated stock frame. The enlarged drawing shows the complete face, the shape to keep, its handedness and the factory edges. The instruction chooses a factory corner as a datum and states where marks fall along stock edges. Join the stated marks and cut on the discarded side so the saw kerf does not shorten the kept piece.
Mirrored triangles remain different cut groups even when their width and height match. Rotated A and B copies of the same stock-frame shape group together. Dimensions are rounded to the tape's display precision; the final wall fit still belongs to the room. Measure several points along every wall, check square, and dry-fit perimeter pieces before batch cutting.
What the quantity does—and does not—credit
The layout counts one fresh stock piece for every installed piece. That is conservative. An offcut can only reduce the order if its remaining factory edges, handed locking profile and size match a later destination. V1 does not solve that nesting problem, so it does not spend an offcut twice on paper. The entered spare percentage is added after the fresh-stock count, and boxes round the result up again. Geometric offcut percentage describes the drawn field; it is not the same as the extra-stock percentage.
The A/B counts are orientation counts, not a purchase instruction for products sold in separately handed cartons. Confirm the supplied split and installation sequence. The planner does not choose adhesive, grout quantity, underlay, subfloor preparation or transitions.
Questions before you set out
Does herringbone always start in the exact centre?
No. Centre establishes a useful reference, but the best working spine depends on where the repeating field meets all four walls. This plan reports the shift and preserves the centred result for comparison.
Is herringbone the same as chevron?
No. Herringbone uses rectangular pieces meeting at 90 degrees. Chevron uses pieces whose ends are already angled so they meet point to point. This solver does not design chevron.
Can I enter nominal tile dimensions?
Only when they are the actual face dimensions. Measure a piece and include the intended joint. A nominal 3 × 6 product may be deliberately undersize to create a 3 × 6 installed module.
Does the length have to divide by the width?
No. Integer ratios make some reference grids convenient, but they are not required for the geometric tessellation. Product approval is separate: a click system may still require its own handed A/B pieces or prescribed sequence.
Does a border fix small perimeter triangles?
A border can replace the outer triangles with a straight field cut, but it also reduces the field, adds border stock and creates corner details. V1 does not pretend that is one checkbox. You can reduce the entered room to explore the inner field, but that is not a complete border design.
Can I use this for an L-shaped room?
No. V1 covers one rectangle without columns, islands or connected doorways. Break an irregular space into measured planning rectangles only for estimating; a continuous set-out needs a combined plan.
For a worked single-versus-double decision, read single or double herringbone.