Gantries are used to clean glass roof areas. This system includes traveling gantries installed on the inner & outer side of the roof of the building. The gantries will be traversing on motorized wheels on the rail track. The track will be installed to the roof structure to the upper roof level with special brackets fixed on the roof structure.Cat Ladders are used to clean the top feature of the building. The manual ladder is installed outside the top feature of the building by means of a pipe rail fixed at the bottom and top of the top features. The ladder will be traversing on the pipe rail by means of rollers.