We do wash the slide toppers, whenever we do the roof, with a gentle long handled brush and awning cleaner. Rinse well.
The slide toppers go in and out with the slides, you cannot leave them retracted, they are NOT like the huge main awning that you can leave in the stored position for months on end. (Dicslaimer on last comment: They do make awnings for the main awning, that are automatic, a bit of wind and they go up. We would not have one, but that is just our decision, they make a lot of them, so obviously there are a lot of people that do like them and want them. Unless a running change has been made, Montana does not install automatic main awnings on their units.)
THERE ARE awnings for the windows, OntMont just got some, and I know there are others that have them as well, these are awnings that you put out at will, and shade the windows.
Slide toppers seem to be lasting, even for full timers like S Reigle for at least 3 years. Steve and Vicki have been out there for bout that amount of time, in all kinds of weather, sun, snow, rain, wind, and he is just now noticing some degradation of the fabric (Steve correct me on this if I am wrong!!!
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