The reference lists of the participant participating EPDM producers for the SKZ were IN TOTAL 39 selected roofing projects in Germany, Austria, the Netherlands and Sweden, ranging in age between 1968 and 1996. The mechanical properties of the samples were tested, such as hardness, tensile strength and elongation at break. Then the samples were subjected to accelerated ageing in the laboratory of SKZ.
As a comparison the mechanical properties were determined from a new EPDM sheet. It should be noted that there can be a maximum of 30 years difference between the production and the samples cut out of the roof. And that therefore slight adjustments in the formulation are to be expected.