Around 6 inches is the ideal thickness for a concrete garage or driveway. This thickness should protect many mid-sized cars and even some heavier ones. However, some garages may only require 4 inches of concrete, while others may need up to 9 inches depending on the weight they are going to bear.
How Thick Should a Garage Floor Be?
A garage floor should be at least four inches thick.
This thickness will provide adequate support for cars and other heavy equipment. The floor should also be made of concrete to provide a durable surface.