How many boxes of flooring do I need for a 12 × 15 ft room?
For the worked example (one 12 × 15 ft room, 22 sq ft per box) the material list is Flooring: 9 boxes (calculated 9 boxes, based on 10% cutting allowance, 22 sq ft per box). Quantities to buy are whole units rounded up from the calculated amounts. Enter your own measurements in the calculator above for your exact list.
How to use this calculator
- Enter each room’s length and width. Use “Add another room” for more than one, or enter the total area if you know it.
- Keep or change the cutting allowance. 10% is a starting value.
- Enter the coverage per box from the product you are considering.
- Copy, print or share the material list.
How this is calculated
- Floor area = sum of (length × width) for each room
- Area to buy = floor area × (1 + allowance ÷ 100)
- Boxes = round up (area to buy ÷ coverage per box)
- Supplied area = boxes × coverage per box
Geometry is deterministic. Material coverage, density, installation waste and product yield can vary. We expose those assumptions so you can replace them with the values printed on the products you are actually buying. Treat every result as an estimate. Items on your list are labelled Calculated (straight from your measurements) or Estimated (depends on an assumption), and “Buy” quantities are whole units rounded up.
Sources
- Home Depot Canada – how to calculate square footage for flooring. Measure each section, add the areas, then add roughly 5–10% extra for waste, and divide by the area per box. The 10% default sits in that range and remains editable.
Last reviewed: . See the methodology.
Assumptions
These starting values are used until you change them. They are typical, not universal. Check the label on the product you are buying.
| Assumption | Starting value | Where it comes from |
|---|---|---|
| Cutting allowance | 10% | Common planning default |
| Coverage per box (optional) | You enter it | You enter it (product / supplier) |
Worked example
A 12 × 15 ft room with a 10% cutting allowance and 22 sq ft boxes:
- Flooring: 9 boxes (198 sq ft required incl. 10% allowance, 198 sq ft supplied) · 10% cutting allowance, 22 sq ft per box
Common questions
How much extra flooring should I buy?
Home-improvement guidance commonly mentions roughly 5–10% extra, and complex rooms or diagonal layouts may need more. It is an editable allowance, not a guarantee.
Can I add more than one room?
Yes. Use “Add another room”. The areas are added together before the allowance.
Are all flooring installs the same?
No. Pattern, plank length and product type change how much you cut away. Check the manufacturer’s guidance for your product.
Guides
- How Much Flooring Do I Need?Room areas, allowance and box coverage turned into a flooring order.
- How to Measure a Room for a Material EstimateFloor, wall and ceiling area from a tape measure and a sketch.
- How Many Boxes of Flooring Do I Need?Required area plus waste, divided by box coverage and rounded up.
- How Much Extra Material Should You Buy?Waste, overage and rounding: what an allowance is and what moves it.
- How Much Extra Flooring Should I Buy?Manufacturer waste guidance for flooring, and what pushes it up.