ESZ Type Z stair bearings incl. side formwork to be supplied and installed for stair flights made of in-situ concrete. The requirements for increased sound insulation according to supplementary sheet 2, DIN 4109, must be fulfilled and verified by a test certificate in the completed building. Proof of the usability of the bearings must be provided. The general building authority approval of the German Institute for Building Technology, as well as a fire protection report are required and must be submitted to the site management.