How Much Concrete for a Retaining Wall?
A 20-foot long, 4-foot tall retaining wall with 8-inch thickness handles moderate soil pressure in residential landscaping. This size is common for terraced yards, garden beds, and driveway edges. Walls over 4 feet typically require engineering, so this represents a popular DIY-friendly height.
Results
Total Volume2.17cubic yards
Total Volume58.67cubic feet
80 lb Bags99bags
60 lb Bags128bags
40 lb Bags198bags
Net Volume (before waste)1.98cu yd
Waste Allowance10%
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