Waterproofing durability: A survey of several APP modified roof membranes in service for more than 20 years in Europe

Eleven APP-modified roofs were randomly selected from a total of 36 for inspection. All of them were installed between 1974 and 1983. Two of them are close to the Alps, two on the sea coast and seven on the plain of river Po. Some samples of membrane were taken from 7 roofs for laboratory investigations about the polymer dispersion grade, cold flexibility, ultimate tensile stress and elongation, joint shear and T peel strength, thickness (if possible). The scope of the work is to verify the conditions of the roof according to the applied maintenance, its influence on the roof and the membrane behaviour, the laboratory test validity on the evaluation of the expected remaining life and to assume the remaining life of the roof according to the applied maintenance, ordinary maintenance, extraordinary maintenance, no maintenance. Comparison between this work on roofs in Italy and similar works (with the same membrane) on roofs in the Netherlands, Belgium, Norway.