Concrete for a 16x24 Slab
Order 5.21 yd with 10% waste — or 214 × 80 lb bags / 285 × 60 lb bags.
By thickness
| Thickness | Cubic yards | +10% waste | 80 lb bags | Typical use |
|---|---|---|---|---|
| 4" | 4.74 | 5.21 | 214 | Patio, shed pad, walkway |
| 5" | 5.93 | 6.52 | 267 | Light vehicle traffic |
| 6" | 7.11 | 7.82 | 320 | Driveway, garage |
Bags or the truck?
For this 384 sq ft slab at 4": bags ≈ $1,391 (214 × 80 lb — that's 17,120 lb of mixing) vs ready-mix ≈ $810 delivered. The truck wins here. Prices are national ballparks — your local quote rules.
Adjust the numbers
Common questions
How much concrete do I need for a 16x24 slab?
A 16x24 slab at the standard 4-inch thickness needs 4.74 cubic yards of concrete — order 5.21 yards with a 10% waste margin. At 6 inches it needs 7.11 yards.
How many bags of concrete for a 16x24 slab?
At 4 inches thick: 214 bags of 80 lb concrete mix or 285 bags of 60 lb. At this volume, delivered ready-mix is usually cheaper and far less work than mixing bags.
Should I use bags or ready-mix for a 16x24 slab?
Ready-mix. Bags for this slab would cost about $1,391 in material and require mixing 17,120 lb by hand; a delivered order runs roughly $810 and arrives ready to pour.