What is the best way to water seal concrete interior walls that are underground? Or is there a way since there is always going to be moisture under the ground where the exterior wall would be?
just some FYI sealing the walls is good. but your just moving the water else were in doing so. you need to make sure that there is a french drain to move it away from your house then seal it up. Laticrete is the best stuff on the market for water sealing. So make sure your french drain is in then seal it.
1st determine the source of the moisture - either its transmitted thru poorly seal'd exterior walls OR is condensation from cool walls & warm air in the bsmt,,, tape a 2.0 x 2.0 plastic sq onto the wall & ck in a few days,,, IF there's wtr behind, its exterior,,, wtr drops on top of the plastic, its inside sourc'd,,, remediation method depends on the source !