Checking those sealant beads

[Me.Bikes.Dogs]

I'm dealing with a bit of water damage to one of the slides right now because of a bead of silicone that had a hole in it. It prompted me to look at the other beads on the trailer and I found a few more holes and gaps. Now I've added a new task to my spring trailer maintenance...check every bead of sealant on the trailer (especially the slides) and re-bead those that look suspicious.

[Festus2]

Kent -
Good suggestion but since you have a silicone sealant, applying another bead of silicone over top of "old" silicone may not be the best idea. Silicone does not adhere well to itself and any sealant you do apply won't last too long before it comes off.

I know it is a lot of work but it may be best to remove the old silicone and start anew with another type of sealant. There are a lot of good non-silicone based sealants out there. But again, even a non-silicone based sealant won't adhere well if you apply it over the old silicone.

It would make RV maintenance much easier if the manufacturers were to use something else other than silicone. Its cheaper so I guess that's why it's used.

[SteveC7010]

And, if those beads of caulk are on the roof of the trailer of the top of the slides, I am certain that they are not silicone. Anything that touches the rubber roofing membrane needs Dicor caulk, either regular or self-leveling.

I'd also suggest taking a closer look at any other caulk used on the outside of the trailer. In most cases, I think you will find that it is butyl caulk, not silicone. Butyl caulk is the best for bonding to two surfaces and retaining a great deal of flex and some stretch.

[Me.Bikes.Dogs]

Yep, you do have to take out the old caulk when re-caulking. In the case of my 2010 Keystone, the caulking around the base of the slide-out is a silicone. Other areas with wider gaps use a butyl.

Sounds like a good time to ask what caulking (not for the roof) people are using?