How Much Concrete for a 20×20 Garage Slab?
A 20×20 foot garage slab is the most common size for a single-car garage. At 4 inches thick, this provides adequate support for vehicle weight while being cost-effective. This is one of the most frequently searched concrete calculations for residential projects.
Results
Total Volume5.43cubic yards
Total Volume146.67cubic feet
80 lb Bags247bags
60 lb Bags320bags
40 lb Bags494bags
Net Volume (before waste)4.94cu yd
Waste Allowance10%
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