Fiberglass Roof Damage

[AFChap]

lead to believe it was a silicon sealer

It is NOT silicone. You don't want to replace it or patch it with silicone based caulk. It is a solvent based sealant that does look a good bit like silicone. I got a tube last year at GNR with lable name Kop-R-Lastic. The description says it is "urethane like" "synthetic rubber".

You can get Eternabond is various widths -- don't know what the widest would be, but I don't believe it would be wide enough to cover all the paint above the drip rail. I wouldn't want to pay for it in that width either!! ...it is pricey enough already! The actual seal overlap that the tape provides has to be pretty narrow ...can someone who has done it say how wide the area is where the tape is on the drip rail (not what is on the roof)?

I haven't done eternabond on mine. I check the roof once a year very thoroughly and spot check throughout the year with sealant replacement once a year or less (one big problem seems to be many Winnebago service departments don't know how, or just don't care, to do the sealant right). My coach is outside all the time, and has averaged about 8,800 miles a year.

[doc]

Paul, My Horizon was a 2000 model, so perhaps Winne has changed since then. I bought a roll of 4" wide and split it to 2". I measured up on the roof 1 inch from where it goes into the channel and made a pencil line the length of the roof. I had cleaned it very thoroughly with Windex and dried it before starting this. I then started applying the Ebond by peeling about 10 inches of backing off and applying the factory edge (straightest since I cut the other) along the line, pulling it to the line and pressing just the edge to the roof. This stuff sticks really tight so make sure it is where you want it when you press. Then I let the other edge lap down into the gutter, pressing out all the air spaces and making sure that both surfaces mated. After about 4-5 feet I went back with a small roller and thoroughly pressed all the surface.
With a 2 inch strip, the Ebond will overlap the edge and almost reach the bottom of the butter. The fabric backed will stretch around and fit the into complex areas better than the 'plastic' backed. I'm not sure what the surface is on that stuff.
I painted on the tintable UV protectant with two coats and was finished. It took me about two days to cut out the old caulk, recaulk and then Ebond the seams. Overkill certainly, but I do not want any leaks.

Leave the silicon alone! The silicon will stick for a a while, but will turn loose and you will have a mess. Ebond will not stick well to it.

[Harry B]

I am considering applying the eternabond just as you described. There are two concerns I have.

One is the overlap onto the aluminum drip rail would only be about ½” . Eternabond instructions require more.

The other is if there is going to be any movement along the length of roof-line, which might chip the painted finish of the eternabond tape.

I have full body paint so I would have to match the eternabond to the existing 4 colors. I don’t mind painting this once and be done with it but I would hate to have to repaint it repeatedly.

Does anyone have experience with my concerns?

[Party Barge]

Thanks for the input. Won't have the ability to look over the rig until Jan, when I pick it up on the way to quartsite. I sure don't mind doing prevention work while the horse in the barn than running across a problem on the road.

[kscouple52]

sorry for the delay in answering....now the Atwood hot water heater got a hole in the tank...only 2 yrs 8 months old im not having to good of luck with this Horizon Am i lol...anyway it was our regular motorhome insurance that paid for roof repair but they might be getting wise to the Winnebago problem because another adjuster that looked at it said he would have denied the claim because it was a factory defect and was happening alot but they had already torn the roof off so they paid...thank god lol anyone have any other questions just write

[Belgique]

This not meant in the slightest way to doubt what has been written here..what has been described is terrible...sure hate for it to happen to me.

I am really surprised and wonder how widespread this is? I've been reading here for a long time and I don't recall reading about this. I do remember the threads about checking the caulking but I thought that was for leaks, not a roof blowing off .......but then, I'm senile half the time.

Hope it isn't like the fogged glass problem that lots of folks have? Again...NO doubt on the veracity of the posts...just wondering about how widespread. Of course, 1 is too many for this kind of thing.

[VectraDon]

Are there any pictures of the typical damage and an Eternabond repair job? I'd like to see what I'm in line for.

[AFChap]

typical damage and an Eternabond repair job?

I have no idea how likely this is to happen (how many out of a hundred?), but suspect the chances are pretty slim if you maintain the roof sealant as recommended. That doesn't mean it can't happen if all maintenance has been properly done, but it is much less likely to in that case. As far as "typical," from what I have observed the problem is not at all typical. Most of us have heard stories of a roof separation, but I have not personally seen it nor do I personally know anyone who has actually seen it apart from this and a couple of other Winnebago lists.

Neither the roof separation problem, nor Eternabond repair (or somewhat more common use of Eternabod as a preventative) are "typical" in my experience, but I do know that they exist out there in Winnebago world.

It would be nice to have a figure that tells us "x out of 100 Winnebago coaches have experienced this problem," and if there is a year of mfg after which the problems either increase or decrease significantly. Does anyone have any idea how to get that kind of information?

[MrTransistor]

Hi All,

I re-caulked the gutter seam by slipping rubber screen door spline between the gutter and the roof fiberglass to hold it pressed in toward the center of the coach while I filled the channel with gold colored RTV silicon caulk. Doing it this way allowed about ¾ inch of bonding surface for both the roof fiberglass and the aluminum gutter. It took 4 tubes of RTV and I have no doubt that it will last as long as I'm still around.

I do believe that all Class A Winnebagos use this same roof/rail design. I'm not sure what Winnebago’s objection is to either silicon sealant or Eternabond. I just know I don't have to inspect the joint for quite a while.

[C Zimm]

Mark: That looks like a really great idea, one that Winnebago could learn from. I did the Eternabond and repaint trip but your idea is the best solution I've seen.
Others can do this and improve an otherwise inferior attachment design.

[jimandsue60]

Looks like a great repair MrTransistor, I might do the same. Is the screen spline a standard diameter?

Jim

[MrTransistor]

Hi Jim,

As far as I know, screen splines are a standard diameter. Around an eighth of a inch and kind of star shaped but with maybe 8 or 10 points. I think I’ve also seen spline that is just round and that would work very well also.

[Art in Mobile]

I don't know the number of folks having a problem with this but I checked mine, a 2006 Voyage and found only about 2 feet of caulk still holding to the rail. I can see that in some cases if the wind gets under the fiberglass and lifts it it would peel off the top thin fiberglass roof. So why not kill two birds with one stone. I cut or pulled off all the old caulk and lightly sanded the area with a folded piece of sandpaper, washed out the rail with a brush and re caulked with 3M 5200. I did not completely fill the void as I wanted to leave the drain holes open. Those of us on this site who have used 3M 5200 in boats know that it is the last caulking job you will ever have to do. The down side is if you ever have to remove it you will have to grind it off. I got it at Home Depot.

[Harry B]

Art,

I considered the same 3M 5200 solution you mentioned. I called 3M to get their thoughts on the Winnebago roof application. I had used it in the past on my boat with nothing but stellar results. The 3M 5200 product tube indicates that it is a permanent application and my experience is as such.

3M however recommended against it for two reasons and suggested using their 4200 product instead.
The first reason given was that 5200 is not UV tolerant so it would have to painted. They thought the paint might come off due to flexing of the joint.
The other reason was that 4200 adheres to metal (aluminum drip rail) better than 5200 and 4200 is in addition UV tolerant.

These were 3M’s arguments to use their 4200 instead of 5200 product. However when I looked up the adhesion ability of the 4200 versus the 5200 the 5200 had almost double the adhesion factor. It left me in a dilemma. Indecision won out and I re-caulked one more time the Winnebago way using their recommended product. Eight months later - the same results, it is starting to let go of the aluminum rail again.

I am still considering the alternatives as discussed during this post. There has to be a better way that is a more permanent solution.

I did however perform a trial project with 3M 5200 on the rounded areas of the rear cap to roof overlap (about 8” on each side). I removed the paint in that area and applied 5200. About 6 months later, the 5200 started to chalk (UV exposure). I Sanded the 5200 caulking and now painted the area to match the body paint (looked much nicer). After our cross country trip this summer the joint is holding up great but as 3M suspected the paint was cracking and chipping slightly due to flexing of the joint. So I sanded it again and repainted the area. The calk job of the 5200 (fiberglass to fiberglass) unlike the Winnebago application is holding up great and the repainting and sanding does not take long.

Mark,

I do like your implementation of caulking the roof line. It provides a lot more contact area. I was under the impression however that silicone usage is not a good idea due to the inability for anything (including silicone sealant) to adhere to it later on should the need arise. Is this not the case with RTV Silicone Caulk?

[ChasA]

Mr Transistor ,et al, I used to manage a hardware store, We carried 3 diameters of screen spline. I have never had any luck with silicone caulk lasting more than 2 years, I hope you have better luck.
Harry B, I recaulked my roof in April or May of this year with the 3M Fast Cure 4000 UV, based on research on their website. So far, so good. Time will tell. I based my decision to try it based on its resistance to UV, its better adhesion to metal, and its elasticity (it will stretch a lot before it breaks).

[Art in Mobile]

Harry B
That is good info. I have used 5200 on some of my wooden show boats and found it sticks better than any other product. As far as the UV problem I think I will put the 2 inch Eturabond (spelling)over it. That will take care of the entire problem. Thanks Harry

[AFChap]

Every time I read of applying new sealant and then covering the sealant with Eternabond, I wonder how long the sealant will last, and what happens when (I think "when" is more accurate than "if") it starts to deteriorate. The sealant likely will last longer under the tape than exposed to sun/weather, but it will at some time deteriorate. At that point, unless the tape is totally watertight, particularly at the ends and where it crosses seams, water can wick under it into the seam.

When should/would the Eternabond tape be removed/replaced? Apparently, by the name, the mfg believes it is eternal/forever, but what if you get that water wicking leak under the end? How would you know before hidden water damage becomes apparent? How would you repair the leaking roof seam short of going through the probably very difficult job of removing the Eternabond. Yeah, I know most owners probably won't have their taped rig by that time (or will they?), but someone will have it. What will be their problem?

Do those who have used Eternabond truly expect it to last forever with no leaking? How many years real use do we have to look at? 5 yrs? 10 yrs? more?

Obviously I am more concerned about having a wicking water leak creating hidden damage for an extended period (because the amount of water would likely be small enough not to be apparent before internal damage is long done) than I am about loosing my roof because it does not have Eternabond on it...

[C Zimm]

Paul: You make really valid points about all of the "what ifs?" It's time Winnebago chimed in with their analysis and give "their" customers some direction.
Please don't misunderstand, I still love my Winnebago but it's time for them to step up.

[MrTransistor]

Hi Harry,

I re-caulked these joints before I discovered irv2.com so I didn't have the benefit of the vast experiences of all the owners here. That was early 2005 as I recall. I think I used a GE Silicones product # GE5097 (Bronze) purchased at Home Depot that was a golden reddish-brown in color that matched our Horizon. The thought of having to glue anything to the silicon in the future didn’t cross my mind. I just remember thinking what a poor attachment the original calking provided.

ChasA,

Thanks for the info. I think a spline that was somewhere around 1/8 inch to 3/16 inch would be ideal. I think 1/4 inch would be too big. If anyone does this fix, just remember to be careful that the spline doesn’t push so far down into the channel as to drop past the lip of the fiberglass.

Paul,

The silicon caulk was ‘Premium Waterproof’ for outdoor use in caulking windows and the color matched the RV. I’ve had no problem with chalking or separation. I bought 4 tubes to make sure I had enough expecting to return any unused tubes. I emptied the last of the 4th tube just as I reached the end of the left side. Even if the silicon were to start to deteriorate, the bead is now about a half-inch or more deep, so it would have to penetrate that far to break the bond between either the rail or the fiberglass.

I can’t see how, given the method of this fix, there could be any wicking. If there were, it would take a high-pressure spray to penetrate at all. We just went through several hours of pouring rain on 12-11-08 from Whitehall, Va. to east of Raleigh, N.C. No leaks anywhere inside the coach. We did have a few damp spots on the floors of the compartments.

Any wicking would have to penetrate to the interior wall material to do any damage since the outside skin is Aluminum bonded to foam which should be quite resistant to dampness. The inside walls seem to be a fiberboard material bonded to the same foam with a vinyl covering and if wetted would probably tend to swell and peel.

I do think the Eternabond solution is quite good and would be much easier and take much less time than the spline and silicon re-caulking. It should hold the roof edge from flipping up in a high wind just as well also. It may be cheaper to use the silicon since I keep hearing about the high cost of the Eternabond. Can anyone tell us how much they used and what the cost was? I think the silicon was around $7.00 per tube and the spline was just a few dollars. Time involved was 4 to 5 hours on a ladder. Something I couldn’t do today.

[Gary CA]

After reading these forum entries I decided to reinforce my seams with Eternabond, just found it advertised as on sale at $27 per 2"X50" roll.

http://www.bestmaterials.com/S...ds=eternabond%20tape

Great forum topic..