Answers to common questions about concrete estimation: how many bags per cubic yard, standard slab thickness for patios and driveways, how to calculate post hole volume, what PSI concrete to use for different projects, and when to order ready-mix instead of bags.
An 80 lb bag yields approximately 0.45 cubic feet. It takes 45 bags to make one cubic yard. Standard residential slab thickness is 4 inches for foot traffic and 6 inches for vehicles.