How Many Square Feet Is a 20x30 Room?
A 20 ft × 30 ft room equals 600 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 20x30 Room
| Metric | Value |
|---|---|
| Floor area | 600 sq ft |
| Floor area (m²) | 55.74 m² |
| Floor area (sq yd) | 66.67 sq yd |
| Perimeter | 100 ft |
| Wall area (8 ft ceiling) | 800 sq ft |
| Wall area (9 ft ceiling) | 900 sq ft |
| Wall area (10 ft ceiling) | 1,000 sq ft |
Common Uses for a 20x30 Space
- 2-car garage + shop
- ADU
At 600 sq ft, this falls in the xlarge category — best suited for two-car garages, workshops, or open great rooms.
How Much Flooring Will You Need?
For a 20' × 30' room, buy enough flooring to cover 600 sq ft plus a waste allowance:
| Flooring Type | Waste % | Buy This Much |
|---|---|---|
| Laminate / LVP (plank) | 10% | 660 sq ft |
| Hardwood | 10% | 660 sq ft |
| Ceramic tile (straight) | 10% | 660 sq ft |
| Ceramic tile (diagonal) | 15% | 690 sq ft |
| Carpet | 10% | 660 sq ft (74 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 20x30 Room?
With 8 ft ceilings you'll paint about 800 sq ft of wall. A gallon covers ~350 sq ft, so you'll need 3 gallons per coat. Plan on two coats for a color change.
Detailed breakdown on our Paint Calculator.
Is a 20x30 Room Big?
This size is typical of a two-car garage or a very large open living space.
How Much Does It Cost to Build a 20x30 Room?
At typical US rates of $150–$300 per sq ft for new construction, a 20x30 addition would cost roughly $90,000–$180,000. For remodels:
- Basic flooring replacement: $1,800–$6,000
- Mid-range remodel: $30,000–$60,000
- Full gut renovation: $60,000–$150,000
Refine with our Cost per Square Foot Calculator.
Frequently Asked Questions
How many square feet is 20x30?
20 × 30 = 600 square feet.
How many square meters is 20x30?
55.74 m².
How many tiles will fit in a 20x30 room?
Depends on tile size. 12"×12" tiles = 660 tiles (with 10% waste). See our Tile Calculator for 6", 18", and 24" sizes.
How much carpet do I need for a 20x30 room?
66.67 sq yd minimum, or 73.33 sq yd with 10% waste for cuts and seams.