The coating is only guaranteed for 5 years. Also unless its hosed down regularly, they get as dirty as any other window. Some people eh?
Call me daft if you like but I really think in the near future glass or glass coating will be invented that is actually self cleaning and does a good job. It just seems like a definite possibility to me. I just wonder how long it will take for the technology to improve to the point where we're not needed any more
As soon as you put eves on a building balcony's it does not work also I find that our rain is mostly from the west so only one elevation gets any cleaning. dry summers also don't clean never mind spiders and bird muck,one of my best customer has all self cleaning glass