We recommend a 4″ court base of steel-reinforced concrete because it offers the best long-term performance. For unstable soil, compaction or water table concerns, we recommend post-tension concrete reinforced with cables. Asphalt can also be used as a less expensive option for tennis courts. Certain conditions may require custom base options, so your personal Wanhe Sport team expert will help you choose the right base for your needs, but steel-reinforced concrete is generally the best option.