When and what to caulk

gitpicker2009 wrote:
I used the Eternabond tape to repair a small tear after encountering a low branch. Are you suggesting that I actually use it in place of or over the existing Dicor sealant around the roof skylights, nose cap etc? I don't mind buying more, the local dealer sells it by the foot.

Some of the more, um, thorough people here will remove the existing Dicor. But if you clean it, especially with the EB prep products, the tape will adhere great to anything on your roof. In my experience on three RVs.

I keep posting warning about Eternabond with sloppy application.
PO used it extensively on my camper and the thing not only did not seal the cracks, but in several areas created pockets, that were pushing water into cracks.
As in all jobs in this life - preparation is crucial.
On my house I used new silicone roof coating from HD.
It is $200 a bucket, but I really like the results. If in the fall the house roof holds well, I will apply the same stuff on my camper.

You can also buy eternabond on eBay and Amazon.

I used the Eternabond tape to repair a small tear after encountering a low branch. Are you suggesting that I actually use it in place of or over the existing Dicor sealant around the roof skylights, nose cap etc? I don't mind buying more, the local dealer sells it by the foot.

t's a mistake to consider all campers to be the same. I don't agree they are designed to leak

True.
My '97 5th wheel trailer roof is 31'10" long and has never leaked and have never replaced all the sealant.
I'm old school...if it doesn't leak don't create one. I do a twice a year inspection looking for hairline cracks in the sealant or open sealant cracks/sealant lifting/damage to the membrane/cracked or broken roof fixtures and jacks.

I have no idea what the OEM sealant was but its done a good job. The few places I've had to add a bit of self leveling Dicor and replace sealant on one side of the skylite that debonded. No leak
Sealant is the 2nd line of defence against a leak. First line line is the grey putty tape (butyl tape) installed between the fixture/jack and the roof.

Pay close attention to the rear and especially the forward cap joint where it joins to the roof membrane.

It's a mistake to consider all campers to be the same. I don't agree they are designed to leak.

My TC is going on 12 years with no leaks and no damage. I touch up caulking from time to time and my TC is stored outside. That being said, RVs vary even within brand. If your TC is 5 years old and hasn't had issues, my guess is you don't have a bad one.

One thing to consider is old caulk is better than new caulk done the wrong way. There are people here who recaulk every year. Is it unnecessary ... that's hard to say. It works for them.

I can tell you first hand that a closely-monitored roof can have a leak under the Dicor sealant, which showed no checking or cracking. This was a corner where water can stand in a small puddle. I now think Eternabond tape is the only prudent way to seal those points.

On places where water does not stand, Dicor lap sealant is a good product, and your thoughts are correct.

As to things on vertical surfaces, do not use lap sealant. Use Proflex RV caulk. Any upward facing edge of anything that is attached to the RV is a candidate for leaking, or caulking, depending on your point of view. :) So this means marker lights, tail lights, windows, door frames, furnace, HWH, fridge grille... anything and everything. If the edge faces upward either straight or angled, water is possible. Awning anchor bolts are usually terribly sealed, at least on the RVs we've owned.

To clarify, let's say you decide to caulk a window frame. You only need to drape the caulk over the top and around the top corners until you get to the sides. No need to caulk the sides and bottom. Apply that same thought process to anything on the vertical surfaces.

The most egregious areas:
Roof seams at front and rear caps, especially corners.
Top of gutter trim pieces below the roof.
Bottom trim on cabover of TC and Class C.
Any corner trim that is upside down or angled upside down.
Any exposed fasteners, like the awning bolts mentioned above.

Of course anything can leak, but those things seem to be the worst offenders.

And I agree with Kayteg that IF you have something leaking, take it apart and renew the internal seal first. But the caulking regimen I described above can be a belt and suspenders approach to prevention.

To start, campers are design with seals (sealing compound) between overlapping joints and caulk should not be used unless you come to corners.
Since all campers are build to leak, owners revert to caulking or ethernabond as the only remedy without taking new camper apart and doing it right.
In your shoes I would do the pressure test with a blower, what has several pictorials on the forum.
Main point is that coulk is not only cheap band-aid on unhealed wound, but also is not lasting remedy.
My 2012 camper being top of the class model already has lot of dryrot damage, regardless aluminium frame.
I bought it with damage already, but it is a disease. It never stops.
After years of having camper in moist climate, we brought it to Las Vegas, where after 3 month of dry heat, lot of things got warped.