Thanks, Gary!
That is timely information for me. I watched the videos and will try to identify my roof material using this info.
I recently cleaned my roof with rubber roof cleaner, assuming it is EPDM. After cleaning, I noticed a lot of small "specks", grayish in color. After further inspection, I noticed I could see a fiber webbing through these worn areas. So, I am now considering re-coating the roof. I have a 2000 Rexhall Aerbus, so I emailed Rexhall to try and confirm just what kind of roof I have so that I can select the right product for the re-coating. I just received a reply that "Rexhall does not use rubber. Only fiberglass". This is very surprising to me, since I had the usual "chalking" that ran off the roof and streaked the sides of the motorhome. I would appreciate any comment you might have.