Our wash is approaching 15 years old and has the old style open metal roof with all the lines and hoses running in an enclosed sheet metal trough. The trough is beginning to rust out and I am exploring better options to go back with. Was considering using 6 in pvc that is bisected in half. Planned on attaching bottom half to sheet metal roof with self tapping screws and then running lines through pvc then capping top with the other half of the six in PVC pipe and either securing with metal straps or heavy duty HVAC type zip ties for easy access. Has anyone seen this type of set up or use any other design. Thanks