Learning from the history of preventive conservation

Preventive conservation is not a new idea. It has been used at least since Greek and Roman antiquity. The author focuses on three main periods: mediaeval, Renaissance/baroque and the nineteenth century. The paper reviews methods of building for isolation, ventilation and climatic stability, drawing on contemporary texts and known examples. Preventive measures are divided into passive, produced by the structure of the building (climate control, moisture barriers, surface protection), and active (periodic cleaning, care and renewal of protective layers). Historical methods with respect to wall paintings, sculpture and pictures are also documented. Practical experience of re-using historical methods with some new modifications is briefly discussed, with reference to the concept of sacrificial layers, indoors and out.