Flooring calculator — packs to buy
Buying laminate, vinyl, engineered or solid-wood flooring means converting a room size into a number of whole packs — and getting it wrong means a second trip or wasted boards. This calculator works out how many packs to order from your room dimensions, the coverage printed on the box, and a waste allowance for cuts and mistakes.
How it works
The tool multiplies room length × width to get the floor area, then inflates it by your waste percentage to allow for offcuts. It divides that adjusted area by the coverage per pack and rounds up to a whole number of packs, since you cannot buy part of a pack:
packs = ⌈(length × width) × (1 + waste/100) ÷ pack coverage⌉
It works in metric (metres, m²) or imperial (feet, ft²) — keep your inputs in the same system. An 8–10% waste allowance suits straight rooms; use up to 15% for diagonal or herringbone layouts.
Example
A 5 m × 4 m room is 20 m². With an 8% waste allowance that becomes 20 × 1.08 = 21.6 m². If one pack covers 2.2 m²: 21.6 ÷ 2.2 = 9.82, rounded up to 10 packs.
| Input | Value |
|---|---|
| Room area | 20 m² |
| Waste allowance | 8% |
| Area with waste | 21.6 m² |
| Coverage per pack | 2.2 m² |
| Packs to buy | 10 |
All calculations happen entirely in your browser — nothing is sent to any server.
Choosing the right waste percentage
The waste allowance is not a safety buffer — it accounts for real material that gets cut off and cannot be reused. The right percentage depends on your layout:
- Straight rows parallel to walls (8%) — offcuts at the ends of rows are often reused to start the next row, so only short end pieces are truly wasted.
- Diagonal (45°) layout (12–15%) — the angled cuts along every wall produce large triangular off-cuts that cannot be used elsewhere.
- Herringbone or chevron patterns (15–20%) — the complex angles on each piece mean most cut ends cannot be reused; waste runs significantly higher.
- Rooms with many bays, alcoves, or pillars — each interruption adds more cut pieces, so add 2–3 extra percentage points per significant protrusion.
What to check on the box
To use the calculator you need coverage per pack, which is stated on every flooring box. On laminate it is usually in m² (for example “2.105 m² per pack”). On luxury vinyl tile (LVT) sold by the tile rather than pack, multiply tile area by the number of tiles per pack to get total pack coverage. If you are mixing plank widths, note that each SKU has its own coverage and must be calculated separately.
Practical tips
Always buy from the same batch. Even the same product code can have slight colour variation between production batches. Order all packs at once so they share a batch number, and check the code printed on each box when collecting.
Keep one spare pack. Set aside one unopened pack from the batch for future repairs. A scratched plank five years from now will be impossible to match if the line has been discontinued.
Measure twice. For irregular rooms, break the floor into rectangles, calculate each separately, and add the results before entering the total. A single large measurement of an L-shaped room will undercount the true area.
Account for thresholds and doorways. Each doorway usually requires a small profile strip, and the flooring runs through the door opening, adding a little to the area. It is better to round up generously the first time than to run short mid-installation.