It is absolutely snake oil. NOTHING you can do to the rubber roof will increase it's service life. Cleaning the roof is purely for cosmetic reasons. I own commercial buildings that have the same EPDM rubber roof membrane as your RV and I have never cleaned or treated any of the 50,000+ sq ft of roofs in over 15 yrs.
you know, i don't doubt what bob said. we bought a 2009 model rig and the previous owner cleaned it. while on the roof i saw no damage but the normal chaulking that occurs as the material ages. it did get dirty, however and i I bookmarked from Jim Beletti, our fearless leader:
//heartlandowners.org/showthread.php/892-Cleaning-the-EPDM-Rubber-Roof?
This past weekend I used the Protect-All products....Cleaner and Treatment...and here's my assessment:
Cleaner worked as described. "Stand-up" application with a sponge mop cleaned the top to bright white except where mildew stained (small penny sized circles which were less visible but still present). 1/2 gallon cleaned our 32 foot top.
Treatment worked as described. Eliminated chaulking and left a somewhat repellent finish. One quart did entire top with 1/3 to spare.
Now, did it perform a miracle. No, it cleaned the top and appeared to present a finish that might repel stains for some time into the future. Manufacturer says 2-3 x /year to reapply.
My assessment....we plan to keep this rig for many years. I'm prepared to invest in anything that makes it look better and MAY extend the incremental life of a component for a year. If it doesnt' I'll feel better and the investment wasn't all that great.
Would I do it again...yes...the time up top "caring" for the top got me to know what's up there better...and I feel better
. If I'd gotten the rig new I'd have done the same thing from day 1.
My 2 cents.
Randy
Randy