Ehhhhhhhhhhh... NOPE.... I do not know that any of us hop up on the roof every 90 days. But we mostly wash the roof a couple times a year. Mild dish detergent, a tad of bleach, a soft brush on a handle and AJAX if you have a stain is great on a rubber roof. Do not use any petroleum based or Citrix based cleaners. There are some UV sealers that we are using to keep the sun from affecting the roof but our roof material is good, tough and will normally last 20+ years.
1994 Fleetwood 33H
1995 Fleetwood 30H (parts vehicle)