Landscaping License Practice Test

What is the minimum subgrade compaction percentage required under concrete pavers?

1. 90%

2. 95%

3. 98%

4. 100%

The correct answer is: 98%

When installing concrete pavers, achieving the appropriate level of subgrade compaction is crucial for ensuring the stability and longevity of the paving system. A minimum subgrade compaction percentage of 98% is typically required to provide a firm and stable base. This level of compaction helps to prevent the movement of the pavers due to settling, heaving, or shifting as a result of weather changes or heavy loads. Compacting the subgrade to this standard increases its load-bearing capacity, reducing the risk of surface deformation or cracking. Furthermore, a well-compacted subgrade minimizes voids and air pockets, which can lead to erosion and the eventual failure of the paved surface. Ensuring that the subgrade meets this compaction standard is therefore essential for a durable and effective installation of concrete pavers.