How much does a cubic foot of concrete weigh?
A cubic foot of normal-weight concrete weighs about 145 pounds: the typical range is 140 to 150 pounds. Bagged concrete mix is about 140 pounds per cubic foot once mixed. In metric, 145 pounds per cubic foot is about 2,323 kg per cubic metre.
How to work it out
- 1 cu ft × 145 lb/cu ft = 145 lb (0.07 tons)
The unit weight is the number every other concrete weight is built from. Iowa DOT measures it on fresh concrete and gives 140–150 lb/cu ft as the typical range for normal-weight mixes, so 145 is a fair middle figure for planning.
Adjust for your project
- Weight in short tons
- 0.07 tons
- Volume
- 0.037 cu yd (1 cu ft)
- Unit weight used
- 145 lb/cu ft (3,915 lb/cu yd)
Weight by cubic feet (145 lb/cu ft)
| Volume | Weight | Weight in short tons |
|---|---|---|
| 0.5 cu ft | 73 lb | 0.04 tons |
| 1 cu ft | 145 lb | 0.07 tons |
| 2 cu ft | 290 lb | 0.15 tons |
| 3 cu ft | 435 lb | 0.22 tons |
| 5 cu ft | 725 lb | 0.36 tons |
| 10 cu ft | 1,450 lb | 0.73 tons |
What changes the unit weight
- Air content. Air-entrained mixes for freeze-thaw exposure hold 5–8% air, which lowers the weight. Iowa DOT’s 140–150 range is stated at that air content.
- The stone. Concrete is mostly coarse and fine aggregate. Dense stone such as trap rock makes heavier concrete; lightweight aggregates (expanded shale or clay) make structural lightweight concrete well below this range.
- Water. Extra water makes the mix lighter and weaker. Quikrete’s data sheets give 140 lb/cu ft for their mixes at the recommended water.
Using the figure
Multiply cubic feet by 145 for weight. A 3 × 3 ft stepping pad 4 in thick is 3 cu ft, about 435 lb. A 12 in tube form 4 ft deep holds 3.14 cu ft, about 455 lb. For whole yards see how much does a yard of concrete weigh, and for slabs, concrete weight per square foot.
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 cubic foot of concrete weigh at the high end?
150 pounds, the top of the usual 140–150 range.
How much do 5 cubic feet of concrete weigh?
About 725 pounds 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)
- Concrete weight per square foot — 48.3 lb per sq ft at 4 in thick
- 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.