Flooring quantity by room size
| Room size | Room area | With 10% extra | 18 ft² / box | 20 ft² / box | 24 ft² / box |
|---|---|---|---|---|---|
| 8 × 10 ft | 80 ft² | 88 ft² | 5 boxes | 5 boxes | 4 boxes |
| 10 × 10 ft | 100 ft² | 111 ft² | 7 boxes | 6 boxes | 5 boxes |
| 10 × 12 ft | 120 ft² | 132 ft² | 8 boxes | 7 boxes | 6 boxes |
| 12 × 12 ft | 144 ft² | 159 ft² | 9 boxes | 8 boxes | 7 boxes |
| 12 × 15 ft | 180 ft² | 199 ft² | 12 boxes | 10 boxes | 9 boxes |
| 12 × 20 ft | 240 ft² | 264 ft² | 15 boxes | 14 boxes | 11 boxes |
| 15 × 15 ft | 225 ft² | 248 ft² | 14 boxes | 13 boxes | 11 boxes |
| 15 × 20 ft | 300 ft² | 330 ft² | 19 boxes | 17 boxes | 14 boxes |
| 20 × 20 ft | 400 ft² | 441 ft² | 25 boxes | 23 boxes | 19 boxes |
These examples use 10% extra. Use the actual carton coverage and an allowance appropriate for your flooring, layout and installation method.
How to calculate flooring
Multiply room length by room width to get square footage. Add your waste allowance, divide by the coverage per carton, and round up to a whole carton.
Example: 12 × 15 room
A 12 × 15 ft room is 180 ft². With 10% extra, plan for 198 ft². If each carton covers 20 ft², you need 10 cartons, giving 200 ft² of purchased coverage.
Calculate your exact room
Enter your room dimensions, waste allowance and the coverage printed on your flooring carton.
Open Flooring Calculator →How much waste should you add?
Waste depends on the material, room shape, pattern, plank or tile size, installer method and whether you want spare material for future repairs. Ten percent is a useful planning example, not a requirement for every project.
For tile quantities and related tools, browse the Flooring & Tile Planning Hub.