Concrete Foundation Volume Calculator

About This Concrete Foundation Calculator

Estimate concrete volume, reinforcing steel quantities, and ready-mix truck count for slab-on-grade foundations. This free calculator handles the complete foundation including slab, perimeter grade beams, and interior beams with automatic code-based recommendations.

How to Use

Select your foundation type (residential garage, residential home, light commercial, or warehouse/industrial) to auto-populate recommended thickness, rebar, and beam sizing per IRC and ACI guidelines. Enter your slab dimensions and beam details, and the calculator provides total concrete in cubic yards with a configurable waste factor, detailed rebar estimates, and ready-mix truck count.

What This Calculator Estimates

• Concrete Volume: Total cubic yards for slab, perimeter beams, and interior beams, broken out separately with waste factor (+5%, +10%, or +15%)
• Rebar Quantities: Linear feet of reinforcing bar by section (slab grid, perimeter beam bars, interior beam bars), total weight in pounds and tons
• Ready-Mix Trucks: Number of standard 10 yd³ trucks needed
• Code Guidelines: Minimum slab thickness, rebar size and spacing, and grade beam sizing per IRC R506, R403, and ACI 302/360

Foundation Types

• Residential Garage: 4″ minimum slab, #3 rebar at 18″ o.c., 12″×12″ grade beams (IRC R506)
• Residential Home: 4″ minimum slab, #3 at 18″ o.c., 18″ deep grade beams (IRC R506/R403)
• Light Commercial: 5–6″ slab, #4 at 12–16″ o.c., 24″ deep grade beams (ACI 360R)
• Warehouse/Industrial: 6–8″ slab, #4 at 12″ o.c., 30″+ deep grade beams (ACI 302/360)

⚠️ Disclaimer: This calculator provides estimates for planning and budgeting purposes only. Always consult a licensed structural engineer for your specific project. Local building codes may require different specifications than the general guidelines shown here.