Ready-Mix Truck Loads for a 20×30 Slab
Freight view of a 20 by 30 ft slab: yards per 10 yard truck and order weight.
Formula SSC-2026.1
Formula SSC-2026.1 · 4,000 PSI
Order volume
10.19 yd³
7.787 m³ placed+waste
Order weight
41,250 lb
18,711 kg
80 lb bags
459
11 pallets at 42 bags
60 lb bags
612
0.45 ft³ yield each
Rebar
840.00 ft
49 × 20 ft · 70 × 6 m · 617 lb
Ready-mix vs bags
$1,680.56
Truck $1,680.56 · 80 lb bags $3,098.25
Grid lines are equalized so the drawing stays readable. The order count uses on-center spacing with a bar at each end of the layout, then holds concrete cover in the field.
| Item | Net | Waste | Order | Unit price | Line total |
|---|---|---|---|---|---|
| Ready-mix concrete | 9.26 yd³ | 10% | 10.19 yd³ / 7.787 m³ | USD | $1,680.56 |
| Short-load fee | Full load | — | 2 truck @ 10 yd³ | USD | $0.00 |
| 80 lb pre-mix bags | 416.7 bags | 10% | 459 bags | USD | $3,098.25 |
| 60 lb pre-mix bags | 555.6 bags | 10% | 612 bags | USD | $3,304.80 |
| #4 rebar sticks, 20 ft | 49 sticks | 10% | 54 sticks / 70 × 6 m | USD | $756.00 |
| Rebar chairs | 294 crossings | 10% | 324 chairs | USD | $90.72 |
| Tie wire rolls | 294 ties | 10% | 2 rolls | USD | $16.00 |
Ready-mix truck
$1,680.56
1.02 nominal 10 yd³ loads · 2 to order
80 lb bags
$3,098.25
60 lb alternative $3,304.80 · delivery weight 41,250 lb
| Thickness | Order yd³ | Order m³ | 80 lb bags | Rebar ft | Ready-mix | 80 lb cost |
|---|---|---|---|---|---|---|
| 4 in | 8.15 | 6.230 | 367 | 924 | $1,344.44 | $2,477.25 |
| 5 in | 10.19 | 7.787 | 459 | 924 | $1,680.56 | $3,098.25 |
| 6 in | 12.22 | 9.345 | 550 | 924 | $2,016.67 | $3,712.50 |
Show the deterministic formula
Slab ft³ = L × W × thickness ÷ 12. Thickened-edge extra = footing band × (footing depth − slab thickness), with corner squares counted once.
yd³ = ft³ ÷ 27. m³ = ft³ × 0.0283168. Weight uses 150 lb/ft³, then the header converts that pound total at 1 lb = 0.45359237 kg. 80 lb bags yield 0.6 ft³ and 60 lb bags yield 0.45 ft³. Currency changes the price labels only.
Bars across a span = floor(span ÷ spacing) + 1. Order sticks = that count, plus 10, 5, or 15 percent waste, cut from 20 ft and 6 m stock. Chairs = one per grid intersection.
Contractor sign-off
Project: Ready-Mix Truck Loads for a 20×30 Slab
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This sheet is an estimate for ordering and layout discussion. It is not a sealed design. Confirm the quantities with a licensed local professional and the authority having jurisdiction before you buy or build.
Engineering notes
A nominal ready-mix truck on this sheet is 10 cubic yards. The 20 by 30 ft slab is 5 in thick with 10 percent waste, so you can read the decimal truck loads and the rounded trucks to book. Short loads under 4 yards suggest a fee you can edit. Ask the plant for the legal payload and the local axle limit before you assume every truck leaves full. The rebar truck is a separate weight on the same page.
Code reference
Planning capacity is 10 cubic yards per truck. Road limits and plant short-load rules control the actual dispatch. IRC R506 and ACI 318 still govern the slab itself.
Field questions
- How full is one truck?
- Divide order cubic yards by 10. A result of 1.3 means two trucks, and the second is not full.
- Does waste change the truck count?
- Yes. Waste is in the order yards. The placed volume is listed separately so you can see the allowance.
- What should I tell the dispatcher?
- Give the order yards, the PSI, the slump the finisher wants, and the short-load fee line if the pour is under 4 yards.