Flooring Calculator

What this calculator does. It tells you how many boxes of flooring to order for a room, given the room size, the coverage printed on each box, and a waste allowance for cuts and offcuts. Works for laminate, engineered wood, LVT, vinyl planks and most click-fit systems.

The formula in plain English. Floor area = width × length. Add a waste percentage for cuts, then divide by the m² per box on the product label and round up to the next whole box. Boxes needed = ⌈(width × length × (1 + waste%)) ÷ coverage per box⌉.

A worked example. A 4 m × 5 m living room is 20 m². With a 10% waste buffer that becomes 22 m² of material. If your chosen laminate covers 2.2 m² per box, 22 ÷ 2.2 = exactly 10 boxes — but because you should keep one spare box for repairs, order 11. For a herringbone install in the same room, jump the waste figure to 20% and the order rises to 11 boxes plus a spare.

Why this matters. Flooring is a one-shot purchase: once you've laid the floor, replacing planks from a different production batch almost always shows. Ordering the right amount in one go — and a spare box for the future — protects the look of the room for the next 10–15 years. It also keeps the price honest: comparing two flooring ranges on a per-m² basis only works once you know exactly how many boxes each one needs after waste.

When to use it. Specifying any new floor, comparing two flooring ranges before buying, double-checking a fitter's quote, or working out whether a discounted clearance range has enough stock left to cover your room.

When not to rely on it alone. Don't use this to specify carpet — fitters measure to wider standard roll widths and minimise seams, which often increases the material needed. For very irregular spaces, sloped ceilings or under-stair cupboards, sketch a floor plan and ask the supplier to confirm; a 15-minute call can save a wasted weekend.

Common mistakes. Using the listing's coverage figure instead of the actual box you're buying (they vary by 20% between ranges), forgetting that underlay, beading and door bars are extra cost lines, and ordering just enough — most installers order a spare box on principle, and so should you. Decorating the same room? The paint calculator and wallpaper calculator use the same room measurements you've already gathered here.