Resealing my motorhome roof turned out to be a labor-intensive project. We just got a new-to-us Lazy Dazes motorhome. It is a 1987 model, so amongst the many other necessary maintenance items to do was to reseal the roof. It didn’t really look too bad when we purchased the motorhome a week earlier, but, on closer inspection, it needed a lot of work.
The roof seams had at least four different sealants slathered on them. They had cracked and separated forming small gullies. Water sat in these gullies until it drained through the seams into the roof and walls of the motorhome. Sometimes you can just coat the seams again, but I decided in this case, I needed to remove all the old sealant and start over.
I started with a regular old putty knife. I would scrape about three to four feet at a time. I'd tighten all the exposed screws. Those that had no grip, I'd replace with a size larger and quarter inch longer one. Next, I'd clean the area with acetone. Finally, I'd seal it with an elastomeric caulk. These short sections took about a half hour per foot. I was doing a good job, but at that rate, it would take a month to finish the project.
At this time, I looked into an oscillating multi-tool, an electric scraper. The Sears Craftsman model would run about $85.00, and take three days to get. I made a run to the far side of town to see if Harbor Freight might have one a little cheaper. I purchased one there with several attachment for less than $35.00. I later spent $18.00 on more attachments for the project. It took some time to learn how to use the tool and the proper angles to attack the different sealants. But, this sped up the removal time so I was doing about four foot in a half hour. I still had to do some hand finishing.
Resealing my motorhome roof took most of three days. I did the two main seams along the total length of the motorhome. I also did around an escape hatch, around two roof vents, around a Fantastic Fan (which was broken, so I replaced it in the process), around two sewer vents, around the TV antenna, around the refrigerator vent, and around several legs for the roof rack. When I was done, I painted two coats of an elastomeric roof coating over the seams and the screw heads for a final seal.
Words of caution: be extremely careful using an electric scraper on a rubber RV roof!
Choose your sealant materials wisely. I used a product from Geocel, because I was sometimes working in freezing temperatures, and this product is rated for these conditions. I used a Dicor product to seal the new Fantastic Fan. If you have a rubber roof, it is especially important to use the proper sealant. If there has ever been any silicone based sealant used in the past, it may be best to continue with silicone sealants, as other sealants will not adhere unless the silicone is totally removed.
This is a very labor-intensive project to do properly. It is hard to get this kind of work done properly by some dealers; they tend to slather more sealant on top of what is already there. When you can find a dealer who will do a competent job, you can expect it to take some time and cost a lot of money. I did it myself so I would know it was done right, to save some money, and to get it done now.
Knowing what is involved will help you know what to expect, and help you decide if you want to tackle resealing your RV roof yourself. It will also help you get the job done properly if you pay someone else to do it for you.
So far, so good. We've been through heavy rains and snow, since I've resealed our motorhome roof, with no leaks.
Editor's note: My husband, Bob Nilles, wrote this article. He does most of the maintenance on all of our vehicles, including our motorhome, travel trailers, or whatever RV we currently have. He also does most of the mechanical repairs on these vehicles.