Flooring Calculator: How Much to Order
Room area to boxes: the calculator uses the real pack sizes of every format in the range and the published waste figures, and rounds up once.
Flooring is sold by the box and laid by the square metre, and the gap between the two is where orders go wrong: a room measured once, a waste allowance guessed, a box short on the last row and a second delivery three weeks later from a different batch. The calculator on this page turns a room into boxes using the real pack sizes of the floors in the range. This text explains what it is doing, so that the number it gives is one you can check.
Add the waste
There is no published industry standard for cutting waste; the figures come from manufacturers' own guidance, and they vary. Havwoods advises 8 to 12 % wastage for plank floors and 15 to 20 % for patterned floors such as herringbone or chevron. Quick-Step's UK guidance for laminate is 5 % extra in a regular room and 10 % in a room with many angles or curves. The calculator offers those as its choices rather than inventing one of its own.
The pattern matters because of how the blocks meet. Herringbone is laid from rectangular blocks with square-cut ends, set at right angles to one another and staggered, so that the end of one block meets the side of the next; chevron blocks have their ends cut at an angle, typically 45 or 60 degrees depending on the manufacturer, so that they meet on a continuous line and form a V. Both patterns run diagonally to the walls, so every wall is a row of angled cuts, and that is where the extra 7 or 8 points of waste go.
Turn it into boxes
Every floor in the range states its box coverage in square metres, and it differs by format rather than by decor. The laminate boards are 2.32 m² a box. The BML rigid vinyl is 2.21 m² for the 5.2 mm planks, 1.74 m² for the wide planks, 1.905 m² for the herringbone blocks and 1.488 m² for the stone-effect tiles. The engineered oak ranges from 1.44 m² to 2.904 m² depending on the width and length of the board, and the parquet from 0.734 m² for the smallest herringbone block to 2.56 m² for a Versailles panel. The solid oak planks are 1.08, 1.2 or 1.44 m² by width, the blocks 1.08 m², and every porcelain floor tile is two tiles to a box at 1.44 m².
The sum is: room area, plus the waste allowance, divided by the box coverage, rounded up to the next whole box. Rounding up is not optional. A box is the unit of sale, and the last row of a floor is not laid from a fraction of one.
What the calculator does not do
It does not price the floor, because prices belong on the product pages and change. It does not size underlay, adhesive, beading or thresholds, which are ordered against the same area but in their own units. And it does not know your room: it assumes rectangles, it assumes the waste figure you chose, and it rounds up once at the end. Where a fitter's own count differs from it, the fitter has seen the room.
Common questions
How much extra flooring should I order?
There is no industry standard; the published manufacturer figures are 8 to 12 % for plank floors and 15 to 20 % for herringbone or chevron from Havwoods, and 5 % in a regular room or 10 % in an awkward one for laminate from Quick-Step. Pick the figure that matches the floor and the room's shape, and round the result up to whole boxes.
Why does a pattern floor need more?
Because the blocks run diagonally to the walls, so every wall is a row of angled cuts and the offcuts from one row rarely fit the next. Havwoods puts patterned floors at 15 to 20 % against 8 to 12 % for planks.
Do I include the space under kitchen units?
Decide first whether the floor is going down before the units or after them. Before, it runs wall to wall and the whole rectangle counts; after, it stops at the plinth. Measure the one you are laying.
Should I keep a spare box?
Yes. Boards from the same batch match; a box ordered later may not. A spare box from the original order repairs a damaged plank years on in the same tone as its neighbours.
Access and delivery are part of the order too, and both depend on where the house is. Browse by town and region.
