Cable Tray as Street Rat
If you build a cable tray on your house, you should be careful of the condition of your cable tray and make sure that your cable tray is completely without hole. The hole that available on your cable tray can become the way for rats to your house. The small hole made larger by rat and they can enter into your house.
Your cable tray should be sealed by sealant made from some polymer in between your cable and the cable tray in order no hole between them. Once the rat can enter your cable tray, rat can broken everything, bite the cable and if they enter your house they can build a nest on your house and breed in there. More longer the number of rats more and more and will destroy everything on your house and will build many hole inside your house, so that they difficult to find because can hide in anyplace on your house.