California Residential Inspector Practice Exam

What is the minimum compressive strength required for a garage floor concrete slab where weathering potential is negligible?

1. 2,000 psi

2. 2,500 psi

3. 3,000 psi

4. 3,500 psi

The correct answer is: 2,500 psi

The minimum compressive strength required for a garage floor concrete slab where weathering potential is negligible is 2,500 psi. This standard is set to ensure that the concrete can withstand typical loads and conditions associated with residential garages, without the risk of damage or failure over time. Concrete with a compressive strength of 2,500 psi is generally deemed adequate for many residential applications, particularly in areas where exposure to harsh environmental conditions is minimal. This strength provides a good balance between performance, durability, and cost, making it suitable for a variety of uses, including garage floors. While higher compressive strengths can be used for specific applications or under more extreme conditions, the requirement for a standard garage floor in a typical residential setting is designed around the assumption of less exposure to severe weathering. Therefore, opting for 2,500 psi provides sufficient strength while remaining practical for common residential construction practices.