Flooring for a 12 × 15 ft room (180 ft²)
Box counts depend on how much each box holds, which is printed on the box (20 to 25 ft² is common for laminate and vinyl plank).
| Layout and waste | Flooring to buy | Boxes at 20 ft² | Boxes at 24 ft² | Boxes at 30 ft² |
|---|---|---|---|---|
| 5% (Straight, simple room) | 189.0 ft² | 10 | 8 | 7 |
| 7% (Typical room) | 192.6 ft² | 10 | 9 | 7 |
| 10% (Diagonal or many cuts) | 198.0 ft² | 10 | 9 | 7 |
| 15% (Herringbone or patterns) | 207.0 ft² | 11 | 9 | 7 |
Before you buy
Measure into doorways and closets, and buy one extra box for future repairs, since dye lots vary. Let the flooring acclimate in the room for as long as the maker says. See the waste factors guide.
Laying it out: rows and the last row
Planks usually run along the long wall (15 ft here), so they stack up across the 12 ft side, which is 144 inches. A last row that is only a sliver looks bad and can lift, so check it before you start. With 48 inch planks you need about 4 planks per row.
| Plank width | Rows across | Width of the last row | Check |
|---|---|---|---|
| 5 in plank | 29 | 4.0 in | Fine |
| 7 in plank | 21 | 4.0 in | Fine |
| 9 in plank | 16 | 0.0 in | No sliver |
If the last row comes out under 2 inches, cut the first row narrower so that the first and last rows are about the same. Leave the expansion gap the maker specifies (usually about 1/4 to 1/2 inch) around the walls.
A 12 × 15 room: the order lands almost exactly on full boxes
A 12 × 15 ft room is 180 sq ft. Add 10% and you need 198.0 sq ft, which is 10 boxes at 20 sq ft a box with almost nothing over, or 9 boxes at 24 sq ft.
Because the allowance uses nearly all of the last box, there is no cushion beyond the 10%: a diagonal layout, a bay or a hearth to cut around means another box, as the 15% line in the table shows. Run the planks down the 15 ft length for the fewest end joints. A living room this size often opens onto a hall, so decide where the floor stops and buy the transition strip at the same time.
Want to change anything else? The calculator above is the full Flooring Calculator: edit any number and the results update instantly.
Tools & materials for this project
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Frequently asked questions
How many boxes of flooring for a 12x15 room?
10 boxes at 20 ft² per box, including 10% waste (198.0 ft² needed for 180 ft² of floor). With 24 ft² boxes it is 9.
How much extra flooring should I buy for a 12x15 room?
5 to 10% for a simple straight layout, and 15% for diagonal or herringbone. For this room, 10% adds 18.0 ft².
How many square feet is a 12x15 room?
180 square feet (12 × 15). Add other rooms, hallways and closets you will floor, and measure into doorways.
Related sizes and guides
Estimates only. Results assume standard materials and simple shapes. Supplier products vary, and the final call on quantity, structure and safety is yours. Check your local code and your supplier's guidance before ordering.