How much does a yard of concrete weigh?

Concrete weight by the numbers

Why 150 lb per cubic foot

That figure is for normal weight concrete made with ordinary sand and crushed stone, and it is the value published across the ready mix industry. Lightweight structural mixes using expanded shale or clay run 90 to 115 lb per cubic foot, and heavyweight mixes for radiation shielding can exceed 300. Unless someone specified otherwise, your pour is normal weight.

What a finished slab weighs

The weight that matters for most people is not a yard, it is their slab. Every row below is 4 inches thick.

A useful shortcut for flat work: a 4 inch slab weighs about 50 lb per square foot. Six inches is about 75 lb per square foot.

Why the weight decides how you pour

Trailer and pickup weight limits

A half ton pickup is not rated for a yard of concrete. At 4,050 lb a single yard exceeds the payload of nearly every consumer pickup, and a small trailer rated for 2,000 lb tops out around half a yard. This is the practical reason bagged concrete stops making sense past about a yard: you cannot legally or safely carry it in one trip either way.

Ready mix truck weight and access

A loaded ready mix truck carrying 9 yards is hauling roughly 18 tons of concrete plus 12 to 15 tons of truck. That combined weight is why drivers refuse soft ground, fresh asphalt and septic fields, and why the chute reach question matters more than most people expect. Cracked driveways from delivery trucks are common and are not the plant's problem.

Form pressure from wet concrete weight

Wet concrete behaves like a heavy liquid, pushing outward on forms at roughly 150 lb per square foot for every foot of depth. A 4 foot wall form is taking about 600 lb per square foot at the base. Forms that look overbuilt for a wall are usually just built correctly.

Existing structures under the load

Adding a topping or a slab over an existing deck, balcony or garage floor adds real load. At 50 lb per square foot for a 4 inch slab, a modest 12 by 12 area adds over 7,000 lb. That is a structural question, not an estimating one.

Concrete weight in metric, and why mixes differ

Outside the United States the same figure is quoted as 2,400 kg per cubic meter. One cubic meter of concrete weighs about 2.4 tonnes, and because a cubic meter is 1.30795 cubic yards, the two numbers describe exactly the same material.

Mixes do vary, and the reason is aggregate rather than cement. Concrete is roughly three quarters stone and sand by volume, so the density of that stone sets the density of the slab. A mix batched with dense granite weighs more than one batched with a lighter limestone, and both sit inside the normal weight range. The spread is small enough that 150 lb per cubic foot is the right planning figure for any ordinary residential pour.

Reinforcement adds less than people expect. A rebar grid at 18 inches on center in a 400 square foot slab is around 375 lb of steel against 20,000 lb of concrete, under 2 percent of the total.

What the weight tells you about ordering

Because weight and volume track each other exactly, the weight of your pour tells you the same thing the volume does about how to buy it. Anything under about a ton is comfortably a bagged job. Past two tons you are into ready mix, and past 18 tons you are into a second truck, which is where the short load and delivery questions start to matter more than the price per yard.

Bagged concrete weight

Bag weights are dry weight. Once you add water, the finished concrete weighs more than the bag.

Forty five 80 lb bags is 3,600 lb of dry material to move by hand, which is the honest reason a one yard bagged pour is a long day. The break even against a delivered short load is covered in the concrete price per yard guide.

How much a yard of concrete weighs: the bottom line

Two tons per cubic yard, 50 lb per square foot at 4 inches thick. Those two figures answer nearly every weight question that comes up on a residential pour, from whether the trailer will handle it to whether the driveway will survive the truck. For the exact weight of your own pour, the concrete calculator reports it next to the volume, and the concrete block calculator does the same for a wall of block.