14 by 24 ft slab at 4 inches
Calculate the requirements for a 14 ft by 24 ft residential slab with #4 bars at 18 in spacing. Ensure compliance with IRC R506 standards. Soil design is excluded.
Formula SSC-2026.1
Formula SSC-2026.1 · 4,000 PSI
Order volume
4.56 yd³
3.489 m³ placed+waste
Order weight
18,480 lb
8,382 kg
80 lb bags
206
5 pallets at 42 bags
60 lb bags
274
0.45 ft³ yield each
Rebar
478.00 ft
37 × 20 ft · 37 × 6 m · 351 lb
Ready-mix vs bags
$752.89
Truck $752.89 · 80 lb bags $1,390.50
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 | Source Spec Material / Tool |
|---|---|---|---|---|---|---|
| Ready-mix concrete | 4.15 yd³ | 10% | 4.56 yd³ / 3.489 m³ | USD | $752.89 | Source Spec Material / Tool |
| Short-load fee | Full load | — | 1 truck @ 10 yd³ | USD | $0.00 | Source Spec Material / Tool |
| 80 lb pre-mix bags | 186.7 bags | 10% | 206 bags | USD | $1,390.50 | Source Spec Material / Tool |
| 60 lb pre-mix bags | 248.9 bags | 10% | 274 bags | USD | $1,479.60 | Source Spec Material / Tool |
| #4 rebar sticks, 20 ft | 37 sticks | 10% | 41 sticks / 37 × 6 m | USD | $574.00 | Source Spec Material / Tool |
| Rebar chairs | 170 crossings | 10% | 187 chairs | USD | $52.36 | Source Spec Material / Tool |
| Tie wire rolls | 170 ties | 10% | 1 rolls | USD | $8.00 | Source Spec Material / Tool |
Source links open a product search on the Amazon storefront for the selected currency. SiteSpecCalc may earn a commission. The link does not change the quantities above.
Ready-mix truck
$752.89
0.46 nominal 10 yd³ loads · 1 to order
80 lb bags
$1,390.50
60 lb alternative $1,479.60 · delivery weight 18,480 lb
| Thickness | Order yd³ | Order m³ | 80 lb bags | Rebar ft | Ready-mix | 80 lb cost |
|---|---|---|---|---|---|---|
| 4 in | 4.56 | 3.489 | 206 | 526 | $752.89 | $1,390.50 |
| 5 in | 5.70 | 4.361 | 257 | 526 | $941.11 | $1,734.75 |
| 6 in | 6.84 | 5.233 | 308 | 526 | $1,129.33 | $2,079.00 |
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: 14 by 24 ft slab at 4 inches
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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
This calculator is designed for a residential slab measuring 14 ft by 24 ft with a thickness of 4 inches. The reinforcement consists of #4 bars placed at 18 inches on center, ensuring structural integrity.
Note that soil design considerations are excluded from this calculation. For proper installation and compliance, refer to IRC R506 for guidelines on concrete slabs.
Code reference
IRC R506
Field questions
- What is the purpose of using #4 bars in the slab?
- Using #4 bars helps to enhance the tensile strength of the concrete slab, reducing the risk of cracking and improving overall durability.
- Why is soil design excluded from this calculation?
- Soil design is excluded because it requires site-specific analysis and testing, which is beyond the scope of this calculator. It's essential to consult a geotechnical engineer for soil-related assessments.
- What are the dimensions of the slab?
- The slab dimensions are 14 feet by 24 feet, with a thickness of 4 inches.
- How often should the #4 bars be placed?
- The #4 bars should be placed at 18 inches on center throughout the slab for proper reinforcement.