How Much Concrete for a 30×40 Workshop Slab?
A 30×40 foot workshop slab provides 1,200 square feet for serious hobbyists or professional workspaces. The 6-inch thickness supports heavy equipment like lathes, milling machines, and vehicle lifts. This thickness prevents cracking under point loads from machinery and toolboxes.
Results
Total Volume24.44cubic yards
Total Volume660cubic feet
80 lb Bags1112bags
60 lb Bags1438bags
40 lb Bags2223bags
Net Volume (before waste)22.22cu yd
Waste Allowance10%
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