Flooring guide
How many boxes of flooring do I need?
Flooring is sold by the carton, and every carton lists the square feet it covers. To find how many to buy, add a waste allowance to the floor area, divide by that coverage, and round up.
Boxes = round up(floor area × (1 + waste ÷ 100) ÷ square feet per box)
Step by step
- Measure the floor area. A 12 × 10 ft room is 120 sq ft. See how to measure a room for flooring
- Add your allowance: 120 × 1.10 = 132 sq ft.
- Read the carton coverage, for example 20 sq ft per box.
- Divide: 132 ÷ 20 = 6.6 boxes.
- Round up: buy 7 boxes, which is 140 sq ft.
Two kinds of extra
The 20 sq ft between the floor and what you buy comes from two places: 12 sq ft of planned allowance and 8 sq ft of rounding to a whole box. The allowance covers cuts; the rounding is simply how cartons are sold. The flooring calculator charts both, so you can see when a different allowance would change the box count.
Quick reference
| Floor area | With 10% | Boxes | Area bought |
|---|---|---|---|
| 100 sq ft | 110 sq ft | 6 | 120 sq ft |
| 120 sq ft | 132 sq ft | 7 | 140 sq ft |
| 150 sq ft | 165 sq ft | 9 | 180 sq ft |
| 200 sq ft | 220 sq ft | 11 | 220 sq ft |
| 250 sq ft | 275 sq ft | 14 | 280 sq ft |
| 300 sq ft | 330 sq ft | 17 | 340 sq ft |
Mistakes that lead to a short order
- Rounding 6.6 boxes down to 6.
- Forgetting closets or the area under a doorway.
- Using a coverage figure from a different product or plank width.
- Ordering a second batch later that does not quite match the first lot.
Planning a budget too? The flooring cost calculator prices the same boxes and adds installation and underlayment.