Commercial Building Inspector B2Footings and FoundationsMedium
During a final inspection of a residential foundation, an inspector observes that the top of the concrete foundation wall is 4 inches above the finished grade. The building plans specified a 6-inch minimum clearance. What is the appropriate action for the inspector?
- ARequire the contractor to raise the foundation wall to meet the 6-inch minimum.
- BApprove the foundation, as 4 inches is generally acceptable.
- CAllow the contractor to backfill to achieve a 2-inch clearance if the grading is sloped.
- DIssue a stop-work order until a structural engineer provides a revised design.
Show answer & explanationAnswer & explanation
Correct answer: A. Require the contractor to raise the foundation wall to meet the 6-inch minimum.
IBC Section 1805.3.1 requires that the top of concrete or masonry foundations be a minimum of 6 inches above the finished grade adjacent to the foundation, or as specified by plans. Since the plans specified 6 inches and only 4 inches is observed, the foundation does not meet code or plan requirements.
Why the other options are wrong
- B. 4 inches is less than the code-required 6 inches and the plan-specified 6 inches.
- C. Reducing the clearance further would exacerbate the non-compliance and potentially compromise the structure.
- D. While a structural engineer might be involved in solutions, the immediate non-compliance is clear and requires correction, not necessarily a revised design for this specific issue.
Foundation Wall Above Grade
The required vertical distance between the top of a foundation wall and the finished grade to protect the structure from moisture and pests.
- Minimum 6 inches for concrete/masonry.
- Minimum 8 inches for wood foundations.
- Prevents decay and termite access.
Memory trick: Keep foundations high, so water can't fly, and critters pass by.