The objective of a research project was to sustainably ensure high-grade recycling of demolished masonry, and especially the clay brick contained in it, so as to return this to brick production where possible. For this purpose, it was necessary to develop a basic knowledge of which qualities and quantities of recycled bricks can be reintegrated in the production process without causing any problems. Depending on the product group, here considerable differences were established. As a result of the tests, a data sheet could be compiled with recommendations for the maximum amount of recycled material that should be added, listed by product group, that is facing or backing bricks or roofing tiles. Depending on the factory’s own brick body composed of raw materials, aggregate and additives, and based on the datasheets, the suitable recycled material can be selected. As limiting factors, influences on the visual appearance of the finished product as well as chemical/physical influences on the production process were taken into consideration. A feasibility study was also compiled.

Silke Sabath, Institut für Ziegelforschung Essen e.V.