You'll need
1.30 cu yd · 59 bags
Cost
$195–$270
Project details
What are you pouring?
Wall dimensions
Quantity
e.g. 8 fence post holes, 3 footings
How you'll buy it
💡 Ready-mix recommended
Your project is ≥1 cubic yard — ready-mix delivery is faster, more consistent, and usually cheaper than 59 bags.
Leave blank to use estimate
Default estimate: $130–$180/yd. Most suppliers have a 1–3 yard minimum.
Reinforcement & site prep
Labor
Cost breakdown
Showing ready-mix pricing (recommended for your volume).
Ready-mix concrete · 1.50 cu yd$195 – $270
Total project cost$195 – $270
💡 Comparison: 59 80-lb bags would cost $354 – $590; ready-mix (1.50 yd) would cost $195 – $270.
Shopping list
Everything you need for this pour.
- Ready-mix concrete (delivered)1.50 cu yd
- Concrete mixing tub or wheelbarrow1
- Mason hoe or mixing tool1
- Gloves, eye protection, knee pads1 set
Ready to pour?
Get quotes from ready-mix suppliers in your area.
Math breakdown
Step-by-step from your inputs.
Wall volume · 12 × 4 × (8"/12)32.00 cu ft each
With 10% waste factor35.20 cu ft
Cubic yards · cu ft ÷ 271.30 cu yd
Estimated weight (wet)5,104 lbs
80 lb bags · ÷ 0.6 cu ft per bag59 bags
Pro tips
8 inches thick minimum. Residential foundation walls: 8-inch standard, 10-inch for taller or basement walls. Retaining walls over 4 feet need engineering and typically 10-12 inch thickness with extensive rebar.
Rebar both directions. Vertical bars every 16-24 inches, horizontal bars every 12-18 inches. Check your specific local code — concrete walls are highly regulated.
Ready-mix only, not bags. Walls take too much volume for bagged concrete to make sense. A typical foundation wall pour is 5-15 cubic yards — bags would mean 250-750 bags. Always go ready-mix for walls.
Frequently asked questions
How much concrete for an 8×40 foundation wall?▾
Assuming 8-inch thick × 40 feet long × 8 feet tall: 8 × 40 × (8/12) = 213 cubic feet, or 7.9 cubic yards. With 10% waste: about 8.7 cubic yards ready-mix.
Concrete block (CMU) vs. poured concrete walls?▾
CMU is cheaper for DIY (no forms needed, no ready-mix truck) but takes longer. Poured concrete is faster on big jobs, stronger, and waterproof when sealed. Most modern construction is poured.
Do retaining walls need drainage?▾
Always. Without drainage, water builds up behind the wall and the hydrostatic pressure cracks or topples the wall. Install perforated drain pipe at the base wrapped in gravel, draining to daylight.
Wall heights without an engineer?▾
Most codes allow up to 4 feet of retaining wall without engineering. Above that, you need a designed wall with calculated rebar and drainage.
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Disclaimer. This calculator provides estimates for planning purposes. Actual material quantities and costs may vary based on site conditions, material availability, and local pricing.