A 30x30 slab covers 900 square feet, and this footprint splits two ways: a three-car garage or shop, or a half-court sport pad in the backyard. Which one it is changes how you pour it more than what the base math says.
Same slab, two very different jobs
For the garage version, the story is load: three vehicles mean pouring heavier than 4 inch flatwork with reinforcement throughout, and thickened edges if the slab carries walls.
For the sport court, the story is the surface. A court has to be flat and consistent across all 900 square feet or every bounce tells on you, and the finish runs smoother than driveway broom while keeping enough texture to not be slick when damp. Colored concrete also shows up on courts, which is the one place on this page the decorative rate earns its row.
The example math
| Finish | Example rate | 30x30 (900 sq ft) |
|---|---|---|
| Standard broom | $9 / sq ft | $8,100 |
| Colored | $12 / sq ft | $10,800 |
Example rates, not market numbers. Building your own rate is the point, and what to charge per square foot for flatwork shows the method.
Volume is now a planning problem
At 900 square feet the concrete order needs real attention. The arithmetic is square feet times thickness in feet divided by 27: just over 11 yards at 4 inches, about 16.7 at 6 inches. You are coordinating multiple trucks at the thicker pour, and the finishing crew has to keep pace with everything that hits the ground. How to figure concrete yardage covers the ordering math so the last truck is not a guess.
Add-ons scale to match: at the example rates, tear-out at $4 per square foot is $3,600 on its own, site prep at $2 is $1,800, and reinforcement at $1.50 is $1,350.
Price the next size in seconds
Whatever dimensions the customer actually has, the concrete slab cost calculator runs them against the same example rates instantly.
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