If historic building structures can not be protected by subsequent sealing against moisture and efflores-cence, the moisture regulation render "Exzellent" from MC Bauchemie is a sound solution. The building substance of the Carmelite monastery in Frankfurt on the Main consists of partly stuccoed rubble masonry. It shows heavy moisture penetration due to missing horizontal and vertical barrier layers, along with efflorescence attributed to high salt concentra-tions. The restoration ext
