A commercial building inspector is reviewing the design of a new retaining wall. The wall is to be constructed of concrete blocks. Which of the following design considerations is most critical for ensuring the stability of the wall?
- AThe height of the wall.
- BThe thickness of the concrete blocks.
- CThe slope of the backfill.
- The presence of a drainage system.
Exam tip
Drainage is a key factor in retaining wall stability.
Why D is correct
Section 1604.1.1 of the 2021 IBC emphasizes the importance of a drainage system in retaining wall design to prevent water from accumulating behind the wall, which can lead to instability. This is the most critical design consideration.