How much does concrete weigh per square foot?
A concrete slab 4 inches thick weighs about 48.3 lb per square foot, at 145 pounds per cubic foot. A 10 × 10 ft slab at that thickness weighs about 4,833 pounds in all.
How to work it out
- 10 ft × 10 ft × 4 in = 33.3 cu ft
- 33.3 cu ft × 145 lb/cu ft = 4,833 lb (2.42 tons)
Weight per square foot depends only on thickness: every inch of concrete adds about 12 pounds to each square foot. That makes it easy to estimate any slab in your head.
Adjust for your project
- Weight in short tons
- 2.42 tons
- Weight per square foot of slab
- 48.3 lb
- Volume
- 1.23 cu yd (33.3 cu ft)
- Unit weight used
- 145 lb/cu ft (3,915 lb/cu yd)
- Over a ton. Check what will carry it — a trailer, a truck’s payload or a floor — before you plan the pour or the removal.
10 × 10 ft slab by thickness (145 lb/cu ft)
| Thickness | Weight | Weight in short tons |
|---|---|---|
| 2 in | 2,417 lb | 1.21 tons |
| 3.5 in | 4,229 lb | 2.11 tons |
| 4 in | 4,833 lb | 2.42 tons |
| 5 in | 6,042 lb | 3.02 tons |
| 6 in | 7,250 lb | 3.63 tons |
| 8 in | 9,667 lb | 4.83 tons |
Per square foot by thickness
| Thickness | lb per sq ft (145 lb/cu ft) | kg per m² |
|---|---|---|
| 1½ in (countertop) | 18.1 | 88 |
| 2 in | 24.2 | 118 |
| 3½ in | 42.3 | 206 |
| 4 in | 48.3 | 236 |
| 5 in | 60.4 | 295 |
| 6 in | 72.5 | 354 |
| 8 in | 96.7 | 472 |
That 12-pounds-per-inch rule (145 ÷ 12 = 12.1) is handy for checking whether a deck, roof or upper floor can take a concrete topping, a hot tub pad or a heavy planter. For anything structural, the allowable load is an engineer’s call — the weight is only half of the question.
For pads you might move as a unit, see how much does a 4×4 concrete slab weigh; for countertops at 1½ in, how many bags of concrete for a countertop works through a 10 ft run. A whole yard is on how much does a yard of concrete weigh.
Different size? Use the full Concrete Weight Calculator.
What you’ll need
- Nitrile-coated work glovesBudget price
Wet concrete and mortar are caustic. Keep the cement off your skin with waterproof gloves, and wash off any that gets in.
See options on Amazon (opens in a new tab) - Contractor wheelbarrowMid-range price
A 6 cu ft steel or poly tray with a pneumatic tire moves concrete from the mixer to the forms. Never load it to the brim with wet concrete.
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Frequently asked questions
How much does a 6 inch concrete slab weigh per square foot?
About 72.5 lb per square foot; a 10 × 10 ft slab is 7,250 pounds.
How much does a 2 inch concrete topping weigh per square foot?
About 24.2 lb per square foot at 145 pounds per cubic foot.
Other common sizes
- How much does a yard of concrete weigh — About 3,915 lb (140–150 lb per cu ft)
- How much does a cubic foot of concrete weigh — About 145 lb (140–150 lb range)
- How much does a 4×4 concrete slab weigh — About 773 lb at 4 in thick
Sources
- Iowa DOT Instructional Memorandum 340 — Weight per cubic foot, yield and air content of concrete (opens in a new tab) — Normal-weight concrete is typically 140–150 lb per cu ft at 5 to 8 percent air.
- Quikrete Concrete Mix (No. 1101) data sheet (opens in a new tab) — Yields: 40 lb ≈ 0.30, 50 lb ≈ 0.375, 60 lb ≈ 0.45, 80 lb ≈ 0.60, 90 lb ≈ 0.675 cu ft; unit weight ≈ 140 lb/cu ft; for pours 2 in thick or more; 6–9 pints of water per 80 lb bag; control joints every 6–8 ft; cure 5 days at 70 °F or above, 7 days at 50–70 °F; protect from freezing for 48 hours.
- NRMCA Concrete in Practice 31 — Ordering Ready Mixed Concrete (opens in a new tab) — Truck mixers carry 8 to 12 cubic yards (about 6 to 9 m³); order 4–10% more than the plan estimate; a loaded truck weighs about 80,000 lb; fresh concrete can cause severe chemical burns.
- NIST Handbook 44, Appendix C — General Tables of Units of Measurement (opens in a new tab) — 1 cubic yard = 27 cubic feet; 1 cubic foot = 1,728 cubic inches.