Protection against the groundwater of historic buildings settled on massive foundations is a challenge. The methods used so far are unreliable and the actions taken do not bring the expected results. Therefore, there is a need to look for new, more effective, and minimally invasive ways of protecting buildings against groundwater. The article presents research on the currently implemented proprietary dual-purpose drainage method. The method involves replacing the clay used in the past with capillary barriers in the form of drainage, in which the filtration chimney is divided into a drying and dewatering zone. This procedure is made possible by the latest generation of materials like waterproof and vapor-permeable membranes separating the drainage bed adjacent to the wall from rainwater.