How to Calculate Concrete Needed
Cubic Yards = (Length × Width × Thickness in feet) ÷ 27
Convert thickness from inches to feet by dividing by 12 first. A 10×10 ft slab at 4 inches thick: (10 × 10 × 0.333) ÷ 27 = 1.23 cubic yards.
Bagged vs Ready-Mix Concrete
For small projects (under 1 cubic yard), bagged concrete mix is usually more practical. For larger pours, ready-mix delivery is more cost-effective and ensures consistent quality throughout the pour.
Frequently Asked Questions
Cubic Yards = (Length × Width × Thickness in feet) ÷ 27. A 10×10 ft slab at 4 inches thick needs about 1.23 cubic yards.
Approximately 60 bags of 60lb mix or 45 bags of 80lb mix equal one cubic yard, since each bag yields about 0.45 or 0.6 cubic feet respectively.
Residential driveways for cars typically need 5-6 inches of concrete thickness. Areas expecting heavier vehicles (RVs, trucks) may need 6+ inches with rebar reinforcement.