mbloom,
The short answer, yes. But, some things need to be taken care of prior to you waxing it. One, make sure it's good and clean which means a good washing with soap and water and maybe a good brush. Then, take a look at it closely. Is there any oxidation on it, any part of it, all of it? Waxing an oxidized surface is really a pain in the a$$.
But, waxing a prepped surface is seriously easier but, still a bit of work. Not many would go through what I've done to mine. Close to 5 years ago, we purchased an '04 Itasca Horizon 36GD with the C-7 330HP CAT. It's a full body paint model. Basically it's been garage/cover kept its whole life. But, the roof had never been maintenance, in any way, shape or form.
So, I got up there and washed it with soap, water and CLEANSER. That got it to a fresh surface. But, I had multiple spots of silicone sealer, tracked all over up there due to careless installers of the King dome satellite system. Well, I had to literally scrape, with a steel scraper, all of them.
Once that was done, out came the paint buffer. Not the cheesy, cheap Autozone type, this one is a Dewalt professional buffer. The same kind the pro painters use on rubbing out paint jobs. That tool and, about a quart of 3M rubbing compound, brought that roof to an ultra nice finish and an outstanding good look.
Once that was all done, out came the Kit car wax. You don't have to get fancy in this part. If a fiberglass roof is in good shape, any car wax will work just fine. As I stated earlier, not many will go through this kind of work on their roof. It's pride thing with me and, a preference. I don't mind the work. It's good for me to get out and get something like this done.
And, it will last for quite some time before re-waxing is necessary.
Scott
In the pictures below, you'll see the starting of the buffing, partially completed. Then, in the rest you see the finished product and, the reflections of the cover over the coach as seen in the shiny surface. Yes, bla, bla, bla, it's more slippery when it's that shiny and waxed but, we ALL KNOW THAT AND TAKE PRECAUTIONS when we're up on any roof.
Scott and Karla SDFD RETIRED2004 Itasca Horizon, 36GD Slate Blue 330 CAT
2011 GMC Sierra 1500 Ext Cab 4x4 Toad
2008 Caliente Red LVL II GL 1800 Goldwing KI60ND