How to Bid Concrete Jobs Profitably: A Full Cost-Loading Method
Most concrete bids die by a thousand small omissions. You price a driveway at $6.50 a square foot because that's what the market seems to bear, cover materials, pay your crew, and still end the month wondering where the margin went. The problem isn't your labor rate — it's everything you forgot to load into the number before you quoted it.
Here's the method, using a 600 sq ft driveway pour (4 inches thick, roughly 7.4 cubic yards) as the working example.
Step 1: Price the concrete itself. At $145/yard delivered, 7.4 yards costs $1,073. This is the number most contractors stop at, then add a flat markup. That's the mistake.
Step 2: Load in truck time, not just material. A ready-mix truck typically bills a base delivery plus a per-minute or per-hour wait charge past the first 5-10 minutes on site. If your pour takes 90 minutes to place and the truck's free time is 15 minutes, you're paying for 75 extra minutes at, say, $2.50/minute — that's $187.50, often billed separately and forgotten when the bid was written.
Step 3: Cost the pump. If you're using a boom or line pump, rental typically runs $800-$1,200/day plus an operator at $75-$100/hour. A half-day pump job (4 hours) at $900 flat plus $350 in operator time adds $1,250 that a gut-feel bid frequently misses entirely, especially on jobs where the contractor doesn't normally need a pump and underestimates it.
Step 4: Load finishing crew labor by the hour, not the job. A 3-person finishing crew at $28/hour each, working 5 hours (screed, float, edge, cure) costs $420. Contractors often price finishing as "part of the day rate" without tracking actual hours, which hides overruns on larger or harder-finish pours (stamped, exposed aggregate, broom finish take longer).
Step 5: Add equipment wear and consumables. Screws, forms, release agent, curing compound, and machine depreciation on trowels/edgers typically run 3-5% of the job's material cost. On this job, that's roughly $35-$55.
Step 6: Total true cost and set margin deliberately. Add it up: $1,073 (concrete) + $187.50 (truck overtime) + $1,250 (pump) + $420 (finishing labor) + $45 (equipment/consumables) = $2,975.50 true cost. If your target margin is 20%, the bid price should be $3,719.38 — not a number backed into from a per-square-foot guess.
Why the gut-feel number fails. A typical guess-bid on this job might land at $3,000-$3,300 based on "$5.50/sq ft feels right." That's break-even or a loss once the pump and truck overtime are counted — the invoice looks fine, the bank account tells the real story 30 days later.
What a spreadsheet for this needs to compute. A proper concrete bid calculator needs to take yardage and pour time as inputs, then compute: material cost from a live per-yard rate, truck overtime cost based on estimated pour duration versus free time, pump rental plus operator cost by job duration, finishing labor cost by crew size and hourly rate, an equipment/consumables percentage, and a final margin-adjusted bid price — with each line item visible so you can see exactly where the cost is coming from before you sign the quote.