CeilingMAX can still be used on a ceiling that has conduit or water pipes runner underneath the floor joists. There are two different ways to go about this. The first option is to shim your floor joists down below the interferences. The second option is to install the top hangers directly to the floor joists. As you are installing the cross tees, you will need to notch out the vertical portion of the cross tee so that it does not interfere with the pipes.