In order to halt the deterioration of the internal finishes and furnishings of a 17th-century house, a remedy to overcome the acute damp problem was needed. Old structures such as this require sympathetic solutions. Newlath 2000 was the system chosen. It is a barrier membrane which does not become an integral part of the actual wall. Newlath 2000 not only provides a secondary wall surface on to which a new finish can be installed, but also produces an air gap between the old wall and itself which enables complete ventilation of the original structure.