How Many Square Feet Is a 12x18 Room?
A 12 ft × 18 ft room equals 216 square feet. Use the calculator below to double-check or customize with waste and cost.
Last updated:Tip: If you only have the diameter, divide by 2 to get the radius.
L-shape = two rectangles sharing a corner.
Add one row per rectangle and we'll sum them.
Key Measurements for a 12x18 Room
| Metric | Value |
|---|---|
| Floor area | 216 sq ft |
| Floor area (m²) | 20.07 m² |
| Floor area (sq yd) | 24.00 sq yd |
| Perimeter | 60 ft |
| Wall area (8 ft ceiling) | 480 sq ft |
| Wall area (9 ft ceiling) | 540 sq ft |
| Wall area (10 ft ceiling) | 600 sq ft |
Common Uses for a 12x18 Space
- great room
- primary bedroom
At 216 sq ft, this falls in the medium category — common for primary bedrooms, family rooms, or dining areas.
How Much Flooring Will You Need?
For a 12' × 18' room, buy enough flooring to cover 216 sq ft plus a waste allowance:
| Flooring Type | Waste % | Buy This Much |
|---|---|---|
| Laminate / LVP (plank) | 10% | 238 sq ft |
| Hardwood | 10% | 238 sq ft |
| Ceramic tile (straight) | 10% | 238 sq ft |
| Ceramic tile (diagonal) | 15% | 249 sq ft |
| Carpet | 10% | 238 sq ft (27 sq yd) |
Need an exact estimate? Use our Flooring Calculator for plank count, or the Tile Calculator for boxes of tile.
How Much Paint for a 12x18 Room?
With 8 ft ceilings you'll paint about 480 sq ft of wall. A gallon covers ~350 sq ft, so you'll need 2 gallons per coat. Plan on two coats for a color change.
Detailed breakdown on our Paint Calculator.
Is a 12x18 Room Big?
This is a large bedroom or medium living room. It comfortably fits a king bed with additional furniture, or a sofa set with a coffee table.
How Much Does It Cost to Build a 12x18 Room?
At typical US rates of $150–$300 per sq ft for new construction, a 12x18 addition would cost roughly $32,400–$64,800. For remodels:
- Basic flooring replacement: $648–$2,160
- Mid-range remodel: $10,800–$21,600
- Full gut renovation: $21,600–$54,000
Refine with our Cost per Square Foot Calculator.
Frequently Asked Questions
How many square feet is 12x18?
12 × 18 = 216 square feet.
How many square meters is 12x18?
20.07 m².
How many tiles will fit in a 12x18 room?
Depends on tile size. 12"×12" tiles = 238 tiles (with 10% waste). See our Tile Calculator for 6", 18", and 24" sizes.
How much carpet do I need for a 12x18 room?
24.00 sq yd minimum, or 26.40 sq yd with 10% waste for cuts and seams.