Ready-Mix Concrete Order Calculator

How it works

The measured volume (converted to cubic yards at 27 cu ft per yard if you enter cubic feet) is increased by the waste allowance. Ready-mix is sold in steps, typically quarter yards, so the volume with waste is rounded up to the next whole multiple of the order increment; an amount already on a step is not rounded further.

Truck loads divide the order by the truck capacity and round up. Full trucks are assumed first, so the last load carries what is left. If the order is below the short-load minimum you enter, the short-load charge is added once to the order.

The delivered cost is the order times the price per cubic yard, plus the short-load charge when it applies, plus any per-load delivery charge times the number of loads. Dividing by the cubic yards ordered gives the delivered cost per yard.

Formula

with waste (cu yd) = volume (cu yd) × (1 + waste ÷ 100)
order (cu yd)      = max(1, ⌈ with waste ÷ increment ⌉) × increment
truck loads        = ⌈ order ÷ truck capacity ⌉
last load          = order − (loads − 1) × truck capacity
short load         = order < short-load minimum
delivered cost     = order × price + [short load] charge + loads × delivery charge

Example

A 4 cu yd pour with 10% waste is 4.4 cu yd, which rounds up to 4.5 cu yd in quarter-yard steps. That fits on one 10 cu yd truck, but it is below a 5 cu yd short-load minimum, so the short-load charge applies.

At the illustrative $165 per cu yd and $100 short-load charge the delivered cost is 4.5 × 165 + 100 = $842.50, or $187.22 per cubic yard ordered.

Assumptions and limitations

• Increment, truck capacity, short-load minimum and every price are inputs, with typical or illustrative defaults: suppliers commonly sell in quarter yards, mixer trucks commonly carry about 8–10 cu yd and short-load charges commonly apply below about 5–6 cu yd, but each supplier sets its own terms and the quote governs.
• The short-load charge is modelled as one flat charge when the whole order is below the minimum. Some suppliers charge per yard short of the minimum, or also charge for a small last load on a multi-truck order; those are not modelled. The last-load figure shows how small that final truck is.
• The waste allowance is a typical figure and is editable. The US Army's FM 5-428, Concrete and Masonry (1998), para 3-20, adds 10% for jobs of 200 cu yd or less and 5% above.
• Waiting time, pump or conveyor charges, admixtures, after-hours delivery and taxes are not included. ASTM C94, the specification for ready-mixed concrete, limits the time between batching and discharge; the limit that applies is set by the edition and project specification in force, and is not calculated here.
• This is an ordering estimate, not engineering, and not a statement of any supplier's terms.

Frequently asked questions