It is very difficult to protect historic buildings set on massive foundations against ground damp. The methods used so far are unreliable, and the taken actions often bring the opposite effects. Therefore, there is a need to search for new, more effective and minimally invasive methods of protecting structures against groundwater. The article presents the proprietary dual-purpose drainage method that is currently being implemented. The method consists on separating the filter zone (chimney) into a drying and drainage zone. It is possible thanks to the newest materials, such as waterproof and, at the same time, vapor-permeable membranes separating the drying bed.