Pipe penetrations from water, sewer and gas pipes in basement walls is a common point of entry for water and dangerous soil gases in a home and a potential health hazard. The reason many of them leak is because they are typically sealed with a temporary patch during the construction of the home. Foundation Wall Pipe Penetration Leaks. When pipes are run through the walls of your foundation, they are typically sealed up with concrete, hydraulic cement, or caulk. Sometimes, they're not sealed at all!