Home Inspection State Practice Exam

A concrete driveway is 1/2 inch higher than the adjacent concrete walkway. What is the most likely cause of this issue?

1. The driveway was poured last.

2. The soil under the walkway was not compacted.

3. Water drainage is affecting the driveway.

4. The walkway is settling due to frost heave.

The correct answer is: The soil under the walkway was not compacted.

The most likely cause of the concrete driveway being 1/2 inch higher than the adjacent concrete walkway is that the soil under the walkway was not compacted properly. When soil is poorly compacted before the installation of concrete, it can lead to uneven settling over time. As the weight of the concrete is applied, any voids or loose areas in the soil can compress more than the surrounding soil, causing the structure above it—in this case, the walkway—to settle lower than its adjacent surfaces, like the driveway. This scenario is typical in concrete installations and highlights the importance of proper soil preparation and compaction to ensure uniform support for any concrete pours. Such settling issues can often be observed in locations where there are uneven loads or insufficient support from the ground beneath. Therefore, the observation of the driveway being higher directly correlates to the potential lack of compaction under the walkway, making it the most plausible explanation for the height difference. Water drainage, while a possible issue for other types of movement or displacement, would generally not account for a consistent height discrepancy observed in this way. Similarly, the timing of the pour or frost heave would not typically cause concrete to be higher than another surface unless they were poured poorly or under specific conditions that directly