Getting Comparable Quotes From Concrete Contractors

A few times a year I take two orders for the same address inside the same week. Two contractors bidding the same driveway, both calling to reserve concrete before they know if they won it. One books 9 yards of 4,000 psi with macro fiber and a mid-range water reducer. The other books 7 yards of 3,000 psi, plain. Same house, same forms, same square footage. From where I sit that spread is not a mystery about labor rates. It is two different slabs.

Homeowners never see that part. You get three totals on three sheets of paper and you pick one. Here is how to force those sheets to describe the same job.

Pin down the geometry first

Everything downstream is meaningless if the bids are measuring different concrete. Before anyone quotes, write down and hand out the same four numbers:

1. Square footage, measured, not estimated from the listing.
2. Thickness. Four inches versus six is 50 percent more material on every square foot, and it is the single most common place two bids diverge.
3. Reinforcement. Fiber in the mix, welded wire fabric, or #4 rebar at 18 inches on center on chairs. These are not interchangeable.
4. Base. Inches of compacted aggregate and whether any subgrade gets removed and replaced.

Hand the same sheet to everyone. A bid that comes back without those four numbers is not one you can compare, and usually not one the contractor intends to be held to.

The mix is a line item, not a detail

This is the part I watch go by on the batch board all day, and it is where quiet money lives. Ready-mix in most US markets runs roughly $155 to $215 per cubic yard for a standard 3,000 to 4,000 psi exterior mix, plus fuel and environmental surcharges of $12 to $30 per load. On top of that sit optional items that a contractor either bought or did not:

• Stepping 3,000 psi up to 4,500 psi: about $15 to $30 per yard.
• Macro synthetic or steel fiber: $8 to $16 per yard.
• Air entrainment for freeze-thaw climates, generally 5 to 7 percent: a few dollars per yard, and non-negotiable anywhere it freezes.
• Hot water in winter or ice in summer: $6 to $18 per yard.
• Short-load fee if the pour is under the plant minimum of 8 to 10 yards: $40 to $100 per yard short.

On a 10-yard residential driveway those options add up to $300 to $700. That is most of the gap between the cheap bid and the middle bid, and none of it shows on a line that says “concrete.” The National Ready Mixed Concrete Association publishes plain-language material on mix specification if you want to read what the terms mean before you argue about them. Our piece on what drives the cost of a concrete driveway covers the labor side.

Ask who pays for the concrete that goes over

Orders come up short constantly, and it is rarely anyone’s fault. Subgrade is never perfectly flat, forms bow outward under the weight, and an over-excavated soft spot swallows an extra half yard without warning. Ordering 5 to 10 percent over calculated volume is normal practice, not padding. So ask each bidder, in writing: is the price fixed for the finished driveway, or per yard delivered? Who eats an extra yard, and who eats the leftover?

Ask about standby, too. Most plants bill waiting time after a free window of roughly 5 to 7 minutes per yard, then $2 to $4 per minute. If a crew is not ready when the truck arrives, someone pays that. On a fixed-price contract, that someone is not you.

Make the schedule part of the comparison

A date is the easiest thing to promise loosely. When a contractor says “we pour Tuesday,” a real Tuesday has an order on a plant board with a yardage and a time slot behind it. Ask what happens if it rains, whether the reschedule is same-week or next-available, and who absorbs a cancellation charge, typically $150 to $400 if a loaded truck is turned away.

Frequently asked questions

Can I ask my contractor for the delivery ticket? Yes, and it is the most useful piece of paper on the job. It lists mix design, strength, yardage, batch time and any admixtures, so you can confirm you received what the bid described.

Is a per-yard concrete price something I can compare between bids? Only alongside the mix design. A $160 yard and a $205 yard are different products, and the cheaper one may be missing the air entrainment or the strength the job needs. Masonry bids hide the same variable in the mortar spec rather than the mix — a Tucson masonry contractor quoting a lime mix against a Portland one is not quoting the same job.

How many quotes make sense for a residential driveway? Three. One is no reference point, two often just splits the difference, and past four you are mostly collecting variations on the same number.

Trade body: National Association of Home Builders.