Caulking

[work2much]

Curious what you folks are using for exterior caulking. I use dicor and eternabond tape where appropriate but what about some of those fine caulking lines that are on the roof and sidewall joints?

I was considering a 100 % silicone exterior caulking like this.



Here is an example of an area I would be resealing.

[Photomike]

We had this same thread a while ago.

A number of manufactures use silicone and many RV techs do. Like one told me when doing some work on my RV and I freaked out about him using silicone. "Been doing it for years, works as well or better than anything else so why would I not use it". The part he siliconed was fine 5 years later when I sold the unit.

I would not hesitate using it on openings on the sides but not sure about a roof.

[jaycocreek]

mkirsch wrote:
I'm sure Bigfoot isn't using off the shelf silicone from Home Depot.

Here's the deal: Household silicone is designed for use on houses that don't move. Dicor and similar products are designed for houses that DO move.

In The 10 Best RV Caulk Reviews & Buying Guide 2019 Gorilla silicone is rated #7 above Etherbond with Dicor as #1..

I mentioned this because the op of this thread linked and pictured just this silicone(Gorilla)...I am trying it and so far it is more than I expected after a very harsh winter here.

30 minute dry time and it can be painted over..

The translucent clear sealant is best to use for sealing cracks and gaps on many surfaces. You can use it for doors, windows, auto, gutters and bath, to name some. It is also waterproof that it can be applied outdoors or indoors.

The sealant does not also shrink or turn yellowish. You can also have peace of mind that it won’t stain the surface to which it is applied. It is also UV resistant that it can last long even with continuous exposure to the changing weathers and outdoor elements.

Aside from the mentioned applications, this product also works well in plumbing and gutters. You also don’t have to worry that it won’t adhere well because it is especially formulated for many types of surfaces. It can also be applied on a damp and slightly oily surface.

Another great thing that I love about this product is that it can be water ready in 30 minutes. That said you could also apply paint on top of it without any worries because it quickly sticks to the surface and dries.

The sealant is also waterproof, so you can look forward to a leak-free RV for a long time by choosing the Gorilla Silicone Sealant Caulk for your camper, automobile and recreational vehicle, and so on.

[mkirsch]

I'm sure Bigfoot isn't using off the shelf silicone from Home Depot.

Here's the deal: Household silicone is designed for use on houses that don't move. Dicor and similar products are designed for houses that DO move.

[jaycocreek]

Bigfoot uses silicone on there campers so It can't be all that bad as the net has proclaimed...

I used the very stuff(Gorilla) the op pictured in his post on my TC just before the storms hit this last year and they were bad..Snow/rain/hail and very deep snow on the roof at one point.To say I was worried about a leak is an understatement but NOTTA anywhere..But I did go through two vent covers..

Due to things beyond my control I was unable to keep my TC covered this winter.

[mi_drew]

I have had good luck using Lexel.

[work2much]

3 tons wrote:
Be careful with etarnabond, as a percaution I’d used it around the perimeter of the bath skylite thinking I’ll now never have a worry about a leak there ever - NOT So!!... A couple years later I noticed water leaking in around the skylite, but assumed the intrusion must have came from some other nearby area and not the skylite...Turned out that my assumption was very wrong and water being shed down from the skylite would hit the surrounding eternabond edge like a dam and then leak thru to the ceiling...A bead of caulking around the inside eternabond surround (where it meets the skylite) stopped the leak for good...

True, in fact I have used eternabond to make roof crickets. You defiantly have to account for how it affects drainage/traps water.

[3_tons]

Be careful with etarnabond, as a percaution I’d used it around the perimeter of the bath skylite thinking I’ll now never have a worry about a leak there ever - NOT So!!... A couple years later I noticed water leaking in around the skylite, but assumed the intrusion must have came from some other nearby area and not the skylite...Turned out that my assumption was very wrong and water being shed down from the skylite would hit the surrounding eternabond edge like a dam and then leak thru to the ceiling...A bead of caulking around the inside eternabond surround (where it meets the skylite) stopped the leak for good...

[work2much]

Thanks for all the input. No Silicone! I have ordered up some proflex, already use dicor and eternabond and sent Lexel a message asking about use on TPO. Their website doesn't list it as a compatible material specifically.

[joelc]

DO NOT USE SILICONE. I use Dicor on the roof and Lexel on the sides.

[3_tons]

I would use self leveling on that because it wont crack and the TPO is not a rigid base... Host can offer some advise too...

[work2much]

Thanks all. Here is an example of a roof seam caulked from the factory. ProFlex does not recommend their product on TPO roofing. I looks like it would work well on other seams like windows or corner moldings.

[3_tons]

Its taken me years to finally master caulking, and the solution was in my hand all along -lol...

First off, I tape off the area to be caulked (doesn’t have to be perfect).

Second, I use Dicor ‘self-leveling’ caulk where there may me a little flexing (like around the side wings, etc) because I found that it remains slightly plyable and doesn’t get so hard to develop crack lines during body flexing and over the loooong term.

Thirdly, apply only a small bead (as in the OP’s picture).

Fourthly, move FAST.

And lastly (this is critical to a ‘factory like’ caulk line), chase with mineral spirits or paint thinner - but here’s the secret ...

MS on on only the index finger will work only for 3-4” until the caulk then begins to gum up and look like h@ll - your frustration will be off the charts... Sooooo, dip all four fingers into the MS, then spread them far apart and then chase the caulk line in one bold stroke using all four spread wide fingers, and go as far as you can until you need to re-wet your finger tips, then continue on...

After reading about far too many failed caulking techniques, and having success with none, this home-brew method produces ‘true’ factory like caulk lines with little practice...

[garym114]

GeoCel ProFlex sealant, comes in colors, easy to smooth out with water spray.
Never silicone.

[h45wt]

downtheroad wrote:
Stick with Dicor or Proflex.

I'm not a fan of silicone or anything exterior on any RV.

If you use Proflex be sure it is Proflex-RV. Regular Proflex dries tacky and will collect dirt that is hard to remove.