The surplus EPS is collected and crushed to grain size in a separate mill. The ensuing ground material is then used for the production of new EPS insulation panels and thus recycled. As a rule, between 5 and 25 per cent of the ground material can be foamed in block form for this process in combination with “fresh” EPS. However, since the use of recycled EPS can also have an effect on the insulation’s impact sound values, the quantity is regulated individually according to requirements. The new insulation panels are then cut in their required thicknesses from the moulded block with recycled content and processed into ready-to-install system panels.