How much flooring for a 18 × 18 ft room?
A 18 × 18 ft room has 324 sq ft of floor. With a 10% waste allowance that is about 15 boxes of flooring at 23.77 sq ft per box — enough material with offcuts covered.
- Room
- 18 × 18 ft
- Net area
- 324 sq ft
- With allowance
- 356.4 sq ft
- Purchased
- 356.6 sq ft
- Leftover (est.)
- 32.6 sq ft
Based on 23.77 sq ft per box (luxury vinyl plank) and a 10% waste allowance for a straight lay. Diagonal or herringbone needs more.
Change the numbers in the flooring calculator →How this is worked out
Flooring calculator uses the same method as every tool here: measure the area, add a visible allowance, divide by what one box covers, and round up. The number above is the honest planning quantity — not an exact cut list. Confirm coverage on your product before buying.
buy = net area × (1 + allowance) ÷ per-box coverage → round up
Other sizes
Related
- Flooring calculator — change any number for your job
- Room material planner — every material on one shopping list
- Calculating square footage for flooring
- Why you buy more than you use
Frequently asked questions
How many boxes of flooring for a 18 × 18 room?
About 15 boxes at 23.77 sq ft per box, covering 324 sq ft plus a 10% waste allowance. Change the box coverage in the flooring calculator for your product.
How much waste should I add for flooring?
10% is a reasonable allowance for a straight lay. Diagonal, herringbone, or a busy room with many cuts needs 15% or more.
Does room shape matter?
This assumes a rectangular 18 × 18 room. For L-shaped or irregular rooms, total the floor area and enter it in the calculator.