How Many Yards of Concrete in a Truckload? Work It Out

A ready-mix truck carries 8 to 12 cubic yards, and most plants dispatch somewhere between 9 and 10.5. The 8-to-12 range is the figure the National Ready Mixed Concrete Association publishes in CIP 31, Ordering Ready Mixed Concrete (2023 revision), which works out to 6.1 to 9.2 cubic meters. The drum is larger than that. Weight is what stops you: concrete runs about 4,050 pounds per cubic yard at the 150 lb/ft³ density ACI 318 uses for normal-weight concrete, and federal law caps a truck at 80,000 pounds gross, 20,000 pounds on a single axle and 34,000 on a tandem. An empty front-discharge mixer weighs roughly 34,000 pounds, leaving about 46,000 pounds of payload — near 11 yards on paper, before the bridge formula and axle spacing take their cut. "Truckload" is a word, not a unit. The number that governs your order is the yardage printed on the delivery ticket.

Five sources, five different answers to "how big is a truck"

Ask five people what a truckload holds and you get five honest numbers, because each one is measuring a different thing.

| Where the number comes from | Figure for one load | What that figure actually measures | |---|---|---| | NRMCA CIP 31 (2023) | 8 to 12 cubic yards | Industry range for truck mixers in service | | Federal weight law, 23 U.S.C. 127 | About 11 yards, arithmetic ceiling | 80,000 lb gross minus roughly 34,000 lb of empty truck | | Drum rating, Oshkosh/McNeilus S-Series | 11 to 11.5 cubic yards | Mixing volume of the drum, which is never the legal payload | | Townsend Concrete's published list (Solano County, CA) | "Up to 12-13 yards per load," and up to 11 with pea gravel | One plant's own dispatch maximum for a specific mix | | Townsend's short-load threshold | 3 to 6 yards, depending on zone | The volume above which they stop charging you a surcharge |

That last row is the one that costs money. The same producer, from the same yard, calls anything under 3 yards a short load in Vacaville and anything under 6 yards a short load out toward Lake Berryessa. Nothing about the truck changed. The billing threshold did.

What the delivery ticket has to tell you, and what it proves

Ready-mix is manufactured and delivered under ASTM C94/C94M, and that standard requires a delivery ticket carrying the batch data with the load. The line that matters most here is the amount of concrete in cubic yards or cubic meters, because CIP 31 is blunt about the basis of sale: concrete is sold by volume of fresh, unhardened concrete, and that basis sits in C94. The ticket also carries the mixture designation, the batch weights, water added at the jobsite, the time of loading, and — since the 2021 revision — the time limit to complete discharge.

That discharge limit is a real change. ASTM C94/C94M-21 revised Section 12.9 and added Section 6.1.10, removing the default 1½-hour limit that had stood since the standard was written in 1933. The purchaser now states the limit, or the manufacturer establishes it and communicates it before delivery, and either way it must appear on the ticket. If you have been assuming ninety minutes because someone told you ninety minutes, read the ticket.

I spent eight years on a receiving dock before I started writing about recalls, and the habit that came out of it is the one I would insist on here: sign for the number that arrived. A signature with no number beside it settles nothing later. CIP 31 puts the same duty on the buyer in one sentence — the purchaser should check and sign the delivery ticket and document any special occurrences on it.

Full load and short load: the same truck, billed two ways

A full load and a short load can arrive in identical trucks, driven by the same driver, from the same plant. The producer's terms decide whether the two are comparable, and the mechanics are usually published if you go looking. Townsend's rate sheet states the rule plainly: a short load fee applies if the concrete delivered is less than the short load threshold, and the fee is $100 or the cost of the difference between threshold and delivery, whichever is less.

Run their published numbers for the Vacaville zone, using their 5-sack 3,000 psi mix at $162 a yard and the $120 zone delivery fee:

• 1 yard: $162 material, $120 delivery, $100 short-load fee. $382 total, or $382 per yard.
• 3 yards: $486 material, $120 delivery, no surcharge. $606 total, or $202 per yard.
• 10 yards: $1,620 material, $120 delivery, no surcharge. $1,740 total, or $174 per yard.

Same concrete, same plant, same week. The delivered cost per yard swings by a factor of 2.2 across that range, and every dollar of it lives in the fee structure rather than in the mix. Those rates are one California producer's; yours will differ. The structure travels, the numbers do not.

Weight sets the ceiling, and in winter the ceiling moves

The Federal Highway Administration's limits on the Interstate System are 80,000 pounds gross, 20,000 pounds on a single axle and 34,000 on a tandem, under 23 U.S.C. 127 and 23 CFR Part 658. The Bridge Formula, added in 1975, can pull the legal gross below 80,000 depending on how far apart the axles sit. Do the arithmetic with a 34,000-pound tare and 4,050 pounds per yard and a 10-yard load grosses 74,500 pounds. Eleven yards puts you at 78,550 and still under the gross cap, which is exactly why axle limits and the Bridge Formula, rather than the 80,000 figure, are what actually decide the dispatch.

Winter helps, briefly. The ground is frozen, the base layers under the roadbed are at their strongest, and posted seasonal routes carry their full rating, which is the only reason a flat, still night like this one has anything to do with a concrete order. Come March it reverses. Michigan's seasonal restrictions under MCL 257.722 cover March, April and May, cutting posted routes by 25 percent on concrete pavement and 35 percent on asphalt. A quote taken in February for a March pour on a posted route can be quoting a load size the truck will not be allowed to carry.

Access cuts the same way. CIP 31 warns that a loaded truck may not manage loose dirt or residential curbs, which is how a nominal 10-yard order becomes two smaller loads or a pump line, with the fees that follow.

The ticket says fewer yards than you expected

This is where documenting beats arguing, and the industry has written down what to check. NRMCA CIP 8, Discrepancies in Yield, splits the problem into real and perceived shortfalls, and the split is testable.

Real shortfalls show up in density. Yield is total batch weight divided by density measured under ASTM C138, and C94 requires the average of three determinations from three different delivery vehicles. CIP 8's own worked example is instructive: a batch of materials weighing 32,220 pounds intended to make 8 yards, measured at 151.0 lb/ft³, yields 7.9 yards. That is the shortfall arriving in the batch, and it is the producer's to correct.

Perceived shortfalls are usually the forms. CIP 8 gives the arithmetic that stops most arguments. An eighth of an inch of extra thickness in a nominal 4-inch slab is a 3 percent shortage, one whole yard on a 32-yard order. Add form deflection, an irregular subgrade, and the roughly 2 percent that hardened concrete loses against its fresh volume through air reduction, bleeding and drying shrinkage, and the concrete can be entirely correct while the forms come up short.

What I do for a living is separate a shipping dent from heat damage. The two are indistinguishable three weeks after delivery and easy to tell apart at the dock. Yield behaves the same way. Before the truck pulls off:

1. Read the yardage on the ticket and compare it against what you ordered, before discharge starts.
2. Photograph the whole ticket, including batch weights and the stated discharge time limit.
3. Record any water added on site, in gallons, and initial it on the ticket.
4. Ask for a density test under ASTM C138 while the load is there, and note the truck number.
5. Write the exception on the ticket itself and keep your copy before you sign.

Working out your own number, and spacing the trucks

Volume first, in the units the plant bills in. One cubic yard is 27 cubic feet, so it covers 81 square feet at 4 inches, 108 at 3 inches, and 54 at 6 inches. A 20-by-24-foot slab at 4 inches is 480 square feet, or 5.93 yards.

Then add the contingency both NRMCA sheets specify. CIP 31 puts the order at 4 to 10 percent above the plan-dimension estimate; CIP 8 repeats it, adding that sporadic work across slabs, footings and fill needs the larger allowance. On 5.93 yards, 8 percent brings you to 6.4, so order 6.5.

Truck interval is load size divided by sustainable placement rate. Ten yards at a placement rate of 30 yards an hour is a truck every 20 minutes. Two numbers bound that interval on either side. The discharge time limit on the ticket sets the outer edge, because a truck queued past its own stated limit is a decision you did not plan to make. Included unloading time sets the inner one — Townsend allows 5 minutes per cubic yard, with 20 minutes on any load of 4 yards or under, then bills $10 for every 5 minutes beyond it. CIP 8 adds the endgame: reassess the volume near the end of the pour and tell the producer in time to adjust the last two or three loads, so you are not chasing a short load after the plant has closed.

The structural questions are not mine. I hand vent sizing to a licensed installer for the same reason: slab thickness, reinforcement and mix strength belong to your engineer, and CIP 31 assigns mixture composition to the producer.

Comparing the next three bids on the same terms

Replace the word truckload in your own request first, then every quote comes back in a comparable shape. Ask for the price per cubic yard by mix designation and specified strength; the short-load threshold in yards and the exact surcharge formula; the delivery or zone fee per load; included unloading minutes per yard and the rate after that; the discharge time limit that will print on the ticket; and weekend, fuel and environmental charges as separate lines. Then quote a total yardage rather than a number of trucks, and let each plant tell you how many loads that is for them.

One check before you treat an old quote as a benchmark. The Bureau of Labor Statistics producer price index for ready-mix concrete manufacturing stood at 401.896 in July 2026 against 393.322 in July 2025, up 2.2 percent over the year. A quote from last summer is stale by roughly that much before anything local is counted, and the index is free to look up.

Questions buyers ask

How much does a 20-yard truck of concrete cost?

No truck holds 20 yards. That volume is two loads, sometimes three. At Townsend's published $162 per yard for 3,000 psi plus two $120 zone fees, 20 yards runs $3,480 delivered, or $174 per yard. Using the national average of about $180 per yard, budget near $3,600 in material plus a delivery fee for each load.

Is ready-mix concrete cheaper than bags?

Above roughly two yards, ready-mix wins. One cubic yard takes 45 of Quikrete's 80-pound bags at 0.6 cubic feet each, which is $269 at Home Depot's $5.98 and 3,600 pounds to move by hand. Three yards runs $807 in bags against $606 delivered on Townsend's list. At one yard it flips: $269 against $382.

How much does a fully loaded 10-yard concrete truck weigh?

About 74,500 pounds. That is roughly 34,000 pounds of empty front-discharge mixer plus 40,500 pounds of concrete, using 4,050 pounds per cubic yard at the 150 lb/ft³ density in ACI 318. It sits under the 80,000-pound federal gross limit, though axle limits and the Bridge Formula usually bind first.

How much area does one yard cover at four inches?

Eighty-one square feet. A cubic yard is 27 cubic feet, and 27 divided by a third of a foot is 81. At 3 inches the same yard covers 108 square feet; at 5 inches, 64.8; at 6 inches, 54. Add 4 to 10 percent for waste and thickness variation, as NRMCA CIP 8 recommends.

Is there a calculator that tells me how many yards are in a truckload?

No calculator can, because the answer is contractual rather than mathematical. A calculator converts your dimensions to cubic yards, which is the useful half. How many of those yards constitute a load is set by your plant's dispatch maximum, its short-load threshold, and the axle limits on the route. Ask the plant.

What is the capacity of a concrete mixer truck in cubic meters?

Between 6.1 and 9.2 cubic meters, converting NRMCA's 8-to-12-cubic-yard range at 0.7646 cubic meters per cubic yard. Worth noting: CIP 31 prints "(5 to 9 m³)" beside that range, and 5 does not match the conversion. Take the yard figure and convert it yourself.

What does the supplier mean by a full load?

Whatever their rate sheet says, which is the volume at or above which no short-load surcharge applies. Townsend sets that at 3 yards in one delivery zone and 6 yards in another, using the same trucks. Get the threshold in yards and the surcharge formula in writing before comparing any two quotes.