Can I apply microcement over existing microcement?

Old microcement can be overlaid if it is solid, not peeling, and free from contamination such as wax, grease, or unsuitable chemicals. The surface needs to be sanded down and usually a new system application is required. Therefore, it is not only about the substrate material but primarily its condition. Before application, check for solidity, flatness, grease, dust, cracks, and any movement. If the surface is risky, it is better to reinforce it or first create a test area. It is likely necessary to apply the full system. In some cases, an adhesion bridge must also be used.