Roof Edges…

Feb. 2017, San Felipe, Mexico

Time to Eternabond the roof edges.

I’ve chosen to tape the edges rather than to use a sealant because there’s some confusion by RV’ers which type of sealant to use, and then the RVs I’ve seen that have had the edges of the roof resealed often don’t look very good. Some say to never use silicone, others say it’s fine. Here’s what someone on one RV forum has to say about the sealants:

“Do not use silicone. The adhesive that Winnie callout sheet (Sealant C) specifies is no longer available. The replacement is NuFlex 640 (Clear) which is a Thermoplastic Sealant”.

Than there have been people who contacted their dealer as well as Winnebago only to have each of them recommended just standard silicone, and recently too. Gah!

So screw it…I’m using Eternabond.

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Down here in Baja, it took some time to have the right weather, and have the labor available to tape my roof edges. But eventually, everything came together and it was time to do it. I’m paying the camp host here at Campo San Felipe to do my taping for me because I often get dizzy these days because of my blood pressure medicine. It keeps my pressure low, like it should, but a side effect is that work where I’m moving my head a lot causes dizziness. Not good when you’re on top of a roof. So, I hired someone to do the job for me. He in turn, hired someone to help him. Same price to me.

A couple weeks ago, I had Carlos (686-152-0481) wash and WAX the roof. I expect the waxing will help keep the fiberglass resilient against rain and excess sunshine. It’s important that the roof be clean when using Eternabond tape and because of the recent wash and wax, it’s a good time to apply tape. I was able to borrow a neighbor’s ladder to work with. What I had the work team do was use a bristle brush to clean out any debris and dirt in the channel along the roof edge, and a clean rag to wipe the edge. There’s a metal channel that runs nearly the entire length of the RV sidewall on both sides, around 1″ tall, and 1/4″ deep, making a “J” shape. The channel is about 1/4″ wide. It helps channel rainwater away from the sides of the RV so the windows won’t get a large amount of rain, which can cause streaks. Sort of a tiny rain gutter. Of course in a heavy rain, it’s kind of worthless but it’s a RV so…What we’ll be doing is putting the 2″ tape into that channel and up the sidewall radius, the length of the RV, on either side. That will put around 1″ of the tape in contact with the fiberglass roof, the other 1″ in contact with the channel, holding the roof securely to the channel.

When I was at the Winnebago Service Center in Forest City, IA, they had a roof profile display and it gives a good idea of what the roof construction looks like. This style roof is typical of the Journey models but the less expensive models have less of the insulating foam installed. I know from Winnebago’s documents that on some cheaper models many of those formed plastic tubes you can see in the picture are hollow…no foam insulation inside them.

I took a picture like this one but can’t find it so I copied someone else’s. The red circle and black arrow are theirs. Hope they are okay with me using it here:

This is how the roof is built and you can see that the roof’s fiberglass cover (Filon) is tucked into that aluminum extrusion (AL) that serves several purposes. The Filon roofing is then caulked all along that edge where it’s tucked in. That caulking ages, dries out, and then just falls out (ask how I know), sometimes in long strips. This is what Winnebago and other manufacturers insist that you inspect and repair if necessary every six months. I didn’t want to do that so when I read up on it, knew I had to do something different. But I digress.

I used 2″ Eternabond tape but some have said they used 4″ for a more pleasing look…though I don’t see how it could be better then the way the 2″ looks.

I had the workers start by putting the edge of the tape in the bottom of the cleaned channel, then the tape is wrapped up towards the curved roof edge. The roof radius, along with the rest of the roof, is covered with that Filon fiberglass sheet. It’s considered a ‘hard’ roof, whereas the rubber type roofs are considered ‘soft’. It has a few cutouts in it for fans, vents, and the like. Some owners will have ACs up there.

You can see from this picture that I waited for a overcast day to do the work. It hovered around 74F the entire time. Might not be necessary but I thought it would be better in the long run.

The edge of the roof we’re taping has caulking that seals the roof material to the sides of the coach (see drawing below). Because the roof expands and contracts due to sun and cold, that seal breaks down over time. This is also why the roof edges are not secured to the roof by clamping with the “J” channel, or with screws. Because the expansion and contraction would pull loose and crack the roof if there were screws holding it in place or if it was clamped to tightly. However, as the caulking ages and the roof eventually pulls loose, that can leave a loose area that road wind can get under and rip the thin roofing right off. I’ve seen several pictures over the years with as much as 33% of the roofing missing. These are a minority of the Winnebagos out there of course, but it’s so inexpensive to do this preventative I couldn’t justify not doing it.

[Edit: Racking the RV on poor roads, or up and down difficult to negotiate driveways can pull the Filon out and away from the edge piece, whether it’s caulking or Eternabond. See Additional Info section below.]

The tape I’m adding reconnects the roof to the edging channel and sticks so well that I am confident it’ll keep the roof from separating from the sidewall, permanently. The tape will also expand and contract right along with the roof. And Eternabond tape is famous for sticking for years, even decades, on clean dry surfaces.

Got it started on the passenger side. I retracted the awning and over-the-door shade to make the work go smoothly.

Running the tape in one continuous 30 foot or so run from front to back helps prevent problems in future, however, if the wind had been blowing, it’s ok to cut the tape into manageable pieces. As the workers moved from front to back of the roof, they make sure the tape is positioned straight, then peel off the protective backing to stick it to the side of the roof, and then roller down the tape, making a watertight seal.This is the tape. It’s 50′ X 2″ and costs around $37 US per roll. I bought 2 rolls from Amazon Prime before I came down to Mexico. This roll is white, but they do make other colors.And now onto the driver’s side. Same procedure, brush and wipe the edge, stick a small length of tape with the protective backing removed in the channel and then work their way down the length of the RV keeping it straight and unwrinkled, removing the backing as they go, sticking the tape to the roof. Followed by using the roller to help it adhere. (I wondered if the wax would keep the tape from sticking, so the brushing was dual purpose. Not sure if it was needed).

Once the tape is down, it’s down forever, I’d warned them, so they were careful. Again they started at the front, though it really doesn’t matter which end you start at. Depends on if you like working from your right or left. I pulled in the slides to make access easier.

The job took those guys 45 minutes to complete. Weather was good, slightly overcast so not too hot, had a nice ladder, no wind. Paid them $500 pesos plus a $100 peso tip. That comes to $30 US with today’s exchange rate of 20.24. And they did an excellent job. No bubbles or ripples. Straight as an arrow. I provided the tape, scissors, clean cloth, roller tool, and borrowed the ladder.

The tape went on easily, according to the workers. Here’s a couple pictures that show it positioned. Might help if you’re doing this job. I can see now that the workers did NOT put the tape all the way to the bottom of the channel as I requested, and I hope that won’t matter over the lifetime of the tape but we’ll see. I have since trimmed that 1/4″ overlap off the near end, Eternabond won’t stick to itself. The end cap tape was a hurried job between huge rainstorms up in Oregon during last years stormy season working alone without a ladder so it has a wrinkle or two.

Here’s a drawing found online, one of Winnebago’s drawings. Thanks to Mile High of RV net forum for posting it first, I found it on a forum thread he’d contributed too. Looking at this profile of how it’s put together, I am wondering why the bead on my rig was so small…I initially thought that Winnie also put it on the back side of the roofing before setting it down on the structure. But that’s obviously wrong. On my roof, there were a couple places where the sealant had weaken and detached from the extruded aluminum edge, and a place or two where road wind had removed it, but no more than maybe a foot overall. Enough to notice if you really inspected that edge, but not noticeable from the ground. I believe I caught the problem in time to perhaps save my roof.

And here’s a look at a special kind of roof edge that Winnie used…

You can see from their notes that they used a plastic spline to hold the Filon in place. Probably 1/4″ in diameter. After inserting the spline they filled the channel with RTV. I imagine this was an attempt to reduce the number of pulled out roofs the other procedure (see drawing above this one) was seeing. I doubt it made much difference so they likely dropped it the next year.

Here’s another look at the new tape edge.

The color of the tape blends in with the roof so it’s really hard to tell it’s up there from the ground. As I said earlier, the long tape edge is positioned in the bottom of the “J” rain gutter and its 2″ width is perfect to stick to the edge of the roof by 1″. I was lucky that the PO never had that edge re-caulked…which is what Winnebago recommends you do every few years, I’ve seen that on other RVs and it’s usually a mess, plus it tends to discolor quickly. The Eternabond face shouldn’t do that, or if it does, it’s easily cleaned. Winnebago also has it as part of their factory warranty that the owner needs to climb up topside and inspect the roof and edges every 6 months. Very few owners do that.

I’m considering doing a bit more on this job and that’s to put a tiny bead of clear silicon on the top edge of the tape. What that does is keep the sticky edge from accumulating grime…which causes a slight discoloration that can be noticeable. But I doubt it would be visible from the ground even without it as you can see the tape sort of rolls up over the edge of the roof radius. And there are all those sidewall devices that obstruct the view as well, the awnings, the slides, etc.

Well, I’ll think on doing that, meanwhile, that little job should give my RV roof the protection I’m hoping for when I’m on the road and the wind picks up. Although it’s rare for this roof to be ripped off in the wind, I’d read about several recent occurrences of it happening to Journey’s around the age of mine so for under $200 US the least I gain is peace of mind.

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Update: Aug. 2020

So it has been more than 3 years since I installed the EB tape along both edges of the roof and so far, tape looks good, still holding well, color is fine, still nice and white. All in all I am pleased with the performance of the EB.

The only maintenance I’ve done to it is the occasional roof washing but that would be done tape or not.

I will mention that I’ve consciously tried to avoid racking the RV but sometimes it’s just unavoidable. I can count on 2 hands the number of times it’s been racked enough that I could hear the straining or had dishes fly out of the cupboards since the tape went on, but I don’t see the tape trying to lift anywhere. I’d expect to see that if I’d racked it too much.

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Update: March 21, 2023

It has now been 6 years since the installation of the Eternabond tape along the edge seam. I just checked it and it’s still fine. Looks good, not lifting anywhere along the nearly 50 feet of application. Still holding firm, no discoloration, bubbles, or lifting.

Part of the reason it’s in such good condition is that I’m very much aware that if I rack the RV too much while driving, that the tape can come loose, along with the roof edge as seen in the below photo in the Additional Information section…so I do my best to take any rough roads or steep angled driveways slowly and carefully. And that seems to be doing the trick.

I’m very happy to not have to worry about the roof of my RV just ripping off one day while traveling down the freeway at 60 MPH and I credit the application of Ebond tape for that.

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Additional information:

Here’s what it looks like when you’ve put the EB tape on your roof line, but your favorite camping spot is difficult to get to, according to BruceH of the iRV2.com RV’ing forum, who says in this thread,

“For me to get to my favorite camping spot, I have to drive 2 miles down a washboard road that is truly wretched. I crawl down this road at about 3 miles per hour to keep the vibration under control.

I am [in] this location every other week for three months of the year.

This is certainly an additional stress in conjunction with the wind.”

 He was not too happy about the EB releasing and having his roof lift up and away as shown in the photo. He supplied the above answer to my question of whether or not his RV had been repeatedly racked.

So if you have a favorite camping spot where getting to it will rack your RV, that is to move the roof one way while the walls move another, then you might have the same situation occur as Bruce did.

Sort of proves that EB won’t completely protect your roof from peeling off in all situations, which is why you should check on how it’s doing regularly. Luckily, most RV’ers that perform this maintenance trick don’t often have their RV racked.