Silicone caulking

kerry4951 wrote:
Capri Campers uses all silicon caulk on their new units.

If this is the case I'de steer clear of Capri Campers. Silicone does not seal reliably. Proflex works. Silicone does not.

I'm with Northshore. My experience is nothing will stick to it, after the fact. The very fact that adhesion will deteriorate over time is the death nell for a wood frame camper, over time. Why? Weather. Sun. Freeze/thaw. Leaks. Seep. Delam. Mildew. Rot. Structural collapse. Death. Unload it for the last time at the dump.
If you only plan to have somebody's old recently siliione laced camper for a short time, silicone caulk will work for you.
There have been exhaustive reports on this TC forum some years back on the use of different caulks for sealing TC's including what products work best in this situation. One guy had a wide ranging photo essay with text of his complete re-caulking process. It was a marvel to behold. Since we have quite a turnover on here with folks coming in a fading out, I would take advantage of the corporate memory of others' experience. I did. Still no leaks.
I put together a saying in college when I still had a fresh mind:
We know what we know. We don't know what we don't know. But, we don't know that we don't know what we don't know.
jefe

Thanks for the heads up on the caulking you've used on your hardy board siding. I have used in the past geocel, that is some pretty good stuff, but for me its hard hard hard to work with, it gets to be too much effort to make it look good not make a huge mess.
For me i use butyl tape (looks like putty) for sealing and the caulking is to protect the butyl tape keep it from weathering or drying out. correct me if I'm wrong on this.

I think I recall people on here previously reporting problems using silicon sealant on aluminum - causing corrosion of the aluminum?

Steve.

I'd just note that I've had a number of aquariums that are put together with silicone. They are most definitely underwater, quite thoroughly stuck together, and, in the case of salt water reef tanks with HID lighting, subjected to substantial UV. No failures yet. Needless to say there's silicone and there's silicone. Dow makes probably 200 different products for different applications, some of the mil spec RTV silicone adhesives are amazing in what they can do, especially where a flexible seal is required.

Yes, I have also seen disasters created with indiscriminate use of caulks and glues of all kinds! As a player piano rebuilder I can't really tell you whether I hate silicone or Elmers glue more.

As a sealer applied in the appropriate places in the appropriate amounts it can be fine, I certainly don't mean to suggest that it's a substitute for a proper repair.

cmcdar wrote:
Please explain the Silicone hate

First off, people use WAY TOO MUCH of the stuff.
Second off, they use it as a generic fix-all for any sort of gap or leak. Rather than address the problem, they gob silicone everywhere.
Third off, silicone is designed for use on a stationary house, not on something that is subject to constant shifting and vibration.

The proper product to use to seal an RV is Dicor or equivalent.

rwiegand wrote:
I've used silicon caulk for many decades, installing bathrooms, kitchen sinks, gutters, some window and door installs, and yes, occasionally when I've needed to make a hole in my TC. It seems to work fine in all of those applications and holds up well for decades of use. It's only as messy as the installer, as far as I can tell. Sometimes it take a couple extra minutes to remove when setting a new fixture after 20 years in place, but doesn't seem to be a big deal-- I want it to stick and seal, after all. t'm still missing what's to hate.

Silicone has four problems: it has poor adhesion, it attracts dirt, and it is difficult to remove entirely, and nothing else sticks to it. While it is very widely used on RVs, it is generally shunned on boats. The real test of a sealant is whether the manufacturer recommends it for below the waterline use on boats, where a failure will sink the boat. No manufacturer of silicone recommends it for this service. Not reliable enough. The product itself lasts well enough in the sun ("30 year warrantee"), but after a short time is no longer adhered to the surface and therefore worse than useless, trapping more water than it sheds.

All that said, NO sealant works well slathered on the outside of a joint. Almost every joint on an RV has an overlap, the sealant belongs between the surfaces in the overlap. If (when) that joint fails, the proper fix is to remove the part, clean the surfaces in the overlap, and re-seal. Anything less is a temporary fix - which unfortunately defines the standard of the RV industry.

northshore wrote:

Now as i remove this and replace the caulking we will see if what ever i choose to caulk with holds up.

Lately I've been using caulk that I had left from James Hardie siding job.
It is pretty affordable (I remember $3-4), you can shape it with finger, or plastic spoon and than you can still press it down following day. I start using it on my camper and seems to hold better than $8 painters caulks.
It is design to withstand UV and exterior use (unlike silicone).
You can order it in several colors at Home Depot, but minimum is 12 tubes case.

The hate about silicone for me with this camper is that as i remove old silicone you can see layer after layer of silicone as you get down to the camper you can see what appears to be the original Lance caulking. This silicone has degraded from the weather and the following is from a silicone site.
"deterioration of sealants can be caused by
prolonged exposure to water, ultraviolet light, and freeze
thaw cycles; evidence of weathering appears in the form of
chalking, discoloration, cracking, or softening."
The silicone on my camper was displaying all of the above characteristics.
my experience has been if you just remove the silicone or if you put silicone over the old it will not stick and fails very quickly, nothing seems to stick to silicone.
My process has been to remove it the best i can and then remove the "film" of silicone.
Now as i remove this and replace the caulking we will see if what ever i choose to caulk with holds up.

I thought I should add, that the people who owned this camper before me apparently thought the silicone was working and sealing, it was not. There are various areas where the silicone has failed and damage has occurred, when the silicone fails it doesn't readily appear bad, but gentle probing will show evidence of failure, instead the previous people just applied more silicone that did not stick. I am not blaming the previous people I probably would have done the same thing until I actually started to learn about silicone.

Stars101 wrote:

billtex wrote:

Kayteg1 wrote:
As I experienced there is still one worse thing in RV than silicone.
It is called eartnabond. (sp)
3rd season after I bought eternabounded camper and still fighting black discoloration on white camper.

Please post picture so we can see damaged EB.

Thanx.

I'd like to see it as well. Please post if you can.

EB discoloration 1

EB discoloration 2

Posted a link to bigger pictures as it would be hard to see on what this forum allows. (you can click + in upper corner to see it really big)
This is 3 seasons after bleaching the discoloration in CA sun.
CA sun is very good bleach. It will clear diesel oil spill on my driveway in 2 seasons, yet the marking EB left are still visible after 3 seasons.
On side notice how the trim is yellowish comparing to the siding.
On cap, you will notice a crack, now glued from the inside, yet in the corner of groove there is still yellow spot left by EB.
On the first season after EB removal those spots were brown/black.
Excuse winter dirt on camper.
Now taking those pictures I noticed that I did not recaulk everything after last repair. Another project once the day gets warmer.