Flooring for a 9 × 12 ft room (108 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) | 113.4 ft² | 6 | 5 | 4 |
| 7% (Typical room) | 115.6 ft² | 6 | 5 | 4 |
| 10% (Diagonal or many cuts) | 118.8 ft² | 6 | 5 | 4 |
| 15% (Herringbone or patterns) | 124.2 ft² | 7 | 6 | 5 |
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 (12 ft here), so they stack up across the 9 ft side, which is 108 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 3 planks per row.
| Plank width | Rows across | Width of the last row | Check |
|---|---|---|---|
| 5 in plank | 22 | 3.0 in | Fine |
| 7 in plank | 16 | 3.0 in | Fine |
| 9 in plank | 12 | 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 9 × 12 room: a guest room or a small dining room
A 9 × 12 ft room is 108 sq ft. Allowing 10% for waste you need 118.8 sq ft of flooring, or 6 boxes of 20 sq ft (5 if the boxes hold 24 sq ft).
As a dining room the floor takes chair legs dragged across it every day, so the wear layer matters more here than in a bedroom, and felt pads on the chairs are cheap insurance. Lay the planks along the 12 ft walls. If the room opens to a hallway that is getting the same floor, measure both together and run the planks through the doorway without a transition strip, where the maker allows it.
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 9x12 room?
6 boxes at 20 ft² per box, including 10% waste (118.8 ft² needed for 108 ft² of floor). With 24 ft² boxes it is 5.
How much extra flooring should I buy for a 9x12 room?
5 to 10% for a simple straight layout, and 15% for diagonal or herringbone. For this room, 10% adds 10.8 ft².
How many square feet is a 9x12 room?
108 square feet (9 × 12). 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.