Laminate Flooring Calculator
Boxes from the room and the carton's coverage, rows and the last-row width, with the waste the lay pattern costs and the expansion gap the count must leave.
Boxes of laminate from the room and the coverage printed on the carton, with the waste the lay pattern actually costs and the expansion gap the count has to leave.
| Floor area | — |
|---|---|
| With waste | — |
| Boxes | — |
| Rows of planks | — |
| Last row width | — |
The number that matters is on the carton, not on this page. Laminate is sold by the box, and a box covers what its label says — 18.7, 20.0, 24.1 square feet, it varies by plank size and count. This page takes that figure as an input because any default would be a guess about a product you have not chosen yet. Read the carton, type the coverage, and the box count is arithmetic.
Waste is the lay, not the room. Every row ends in a cut, and the offcut starts the next row only if it is long enough to keep the end joints staggered. In a plain rectangle laid straight that costs about a tenth; a diagonal lay or a room full of closets and returns costs more, because the offcuts are triangles nobody can reuse. The three allowances above are the usual figures for those three cases, and they are allowances, not specifications.
The last row is where the plan shows. Divide the width by the plank width and the remainder is the strip along the far wall. A sliver under a third of a plank looks wrong and snaps badly; the fix is to rip the first row narrower so the two edge rows share the cut. The page prints the last-row width so that decision is made before the first plank goes down, not after the last.
Leave the gap. A floating floor moves with humidity and needs an expansion gap at every wall, typically ¼ to ⅔ inch, per the manufacturer’s instructions. It does not change the box count much; it changes whether the floor buckles in August.
Boxes = ceil(area × (1 + waste) ÷ coverage per box). Rows = ceil(room width ÷ plank width); the last row is the remainder of that division. Coverage per box is the carton’s figure. Waste allowances and the expansion gap are common practice and the manufacturer’s instructions respectively, not standards.
Worked example
A 15 × 12 ft room in laminate sold at 20 ft² a box: how many boxes?
- Area = 180 ft²; with 10% for a straight lay, 198 ft².
- 198 ÷ 20 = 9.9, so 10 boxes — 200 ft² bought, 2 ft² over.
- 7½ in planks across 12 ft: 144 ÷ 7.5 = 19.2, so 20 rows, and the last row is a 1½ in sliver.
10 boxes. The last row would be a sliver, so rip the first row narrower and let the two walls share the cut — the page flags it. Coverage per box comes off the carton, and that is the only number that decides the count.
Questions
How many boxes of laminate for 180 square feet?
10 boxes at 20 ft² a box with 10% waste (198 ft²). The coverage per box is on the carton and varies by product.
How much waste for laminate?
About 10% for a straight lay in an ordinary room, 5% for a clean rectangle, 15% for a diagonal lay or a room with closets and angles.