If the basement has ever experienced any groundwater seepage at all, then it needs a quality basement waterproofing system like WaterGuard® . The idea is that basement water problems never get better, they only get worse as the house ages and the drains and coatings that protected the house fail. Therefore, even if water seepage is a once a year occurrence, it needs to be fixed before the basement is finished, as flooding is likely to be more frequent in the future. Some cautious homeowners put in such a system even if they have not had seepage, just in case. This makes sense from the standpoint that these systems are far easier to put in a basement that is unfinished than one where finished walls and floor coverings restrict access afterwards. It is also highly recommended that this system be installed around the entire perimeter of the basement.