Caulking - tips and tricks

LG · 09-29-2013, 09:07 AM

Caulking is a maintenance thing. Caulk early and often. You get it in shape and then just do inspection and caulk as necessary on a yearly basis. I use GE silicone II I bought at Home Depot. Does a good job and excess cleans up easily off the trailer and my hands with a rag dampened in mineral spirits.

My method of caulking - I rarely try to "lay a bead" with my caulk gun. This gets too much caulk on there and ends up creating a big mess. Only when I need a lot of caulk on something do I actually lay out a bead. Even then the bead is just to get some caulk out there. My finger is my best tool. Most of the time the application is best done by just squeezing a small amount onto your finger first and then "tooling" it in (rubbing into the crack) with your finger, then wipe off excess with a rag dampened with mineral spirits. Release the pressure on your caulk gun's piston each time after you get a little on your finger or else a big glob will continue to spew out and you'll have caulk dripping all over the place.

Also, After you get it on there, be sure to wipe off the excess. You only need caulk in the cracks. You don't need to have caulk encasing everything, just filling the cracks. The roof not so much, you can glob it all over the roof if you want because you don't need to worry about the aesthetics on the roof - just the water - but on the sides, wipe off everything you can without lifting it completely out of the cracks so it looks nice and neat when you're through. If you leave that thin coating on the surface, you won't see it immediately, but later when it begins to gather dust it will make your trailer look like amateur hour on the caulk job with caulk smeared all over the thing. You don't need the caulk to taper off a half inch beside the crack - just fill the crack and wipe off the rest. If you use good caulk that will seal it. AND CAUTION, when you go to wipe your finger across whatever it is your caulking in order to push that caulk down into that crack BE SURE that edge is not a sharp one. My personal experience is that you can get a nice razor type cut right on the tip of your index finger if you're not careful about what your doing. On the sharper edges, try to wipe your finger perpendicular or at an angle to the edge to avoid getting cut. If you do get a little cut don't worry, the mineral spirits will sterilize it! You'll know it by the stinging. Of course, you'll have to get a Band-Aid and switch to another finger after that.

On my trailer, no one had caulked it in a long time and all of the previously applied caulk on the roof had cracked (non-silicone) so, rather than dig all that old stuff off I filled the cracks and gave it a fresh coat of silicone over the top of it all. I caulked liberally around each vent and every object that comes through the roof and then around the perimeter where the water sheds over the side. Should be fine especially if I re-inspect every spring and fall.

I also took the rubber trim off the corner moldings on the front and rear and found many rusted screws - some of which weren't even getting any "bite" anymore. Replaced non-holding screws with screws a bit longer (got lucky there - not enough damage to rot it out), caulked around the heads of all of the screws and then replaced the trim piece. Re-caulked the tops of the moldings up at the roof corners REAL good. This is where the water will most likely enter. Then also caulked the sides where the aluminum skin tucks under the molding.

From a tip on here, I took off the rear spare tire mount, injected some caulk into the rusted screw holes and reattached it, used enough caulk so that the caulk squeezed out slightly as they were tightened, and then caulked the top and sides of both the top and bottom attachment points on that thing wiping it all off with mineral spirit rag.

Then I caulked the top edge and sides of everything that is attached to the outside. All the vents, the hot water heater, the fridge vents, the lights, the windows, the door, the storage cubby, everything. Wipe on - wipe off.

Then I took the hose and sprayed water over the top and watched how it ran off and did some more caulking in some spots that I thought MIGHT leak. I try to think like the water.

The bottom line is you have to do it regularly. These things are water tight when they come out of the factory (usually) but then the weather takes it's toll quickly. If you stay on top of the caulking you will not end up with leaks and more expensive repairs later on. If you don't like doing a little maintenance on your toy to keep it nice maybe the camper thing is not for you - either that or, if you have the money you could buy a new one and just trade it in very few years for another new one, I guess. For me, part of the fun of owning my little trailer is keeping it nice and "making it mine". I'm kind of proud of the fact that I took an older trailer that was quickly going down the tube and without too much trouble fixed 'er up so she'll last quite a bit longer. Good as new. Saved me a bunch of money compared to a new one and I now have that "pride of ownership" feeling to enjoy.

Reply here and let me know if I can ever help you out.
LG

lee1 · 09-30-2013, 07:22 AM

Lg, Thanks for the advice!

Eagle · 10-01-2013, 07:10 AM

I use Butyl rubber caulk when making a few exterior alterations....but my unit hasn't needed any re-caulking...well not yet anyway.

webslave · 10-01-2013, 03:08 PM

Butyl rubber caulk would be my first choice also...

One of the problems with silicon caulk, wait for it...is the silicon it contains. On initial application to a surface it will hold up fairly well, however, in parts that move or if you need to have another "coat" put on, the silicon will prevent the adhesion or reapplication aherance. That's the nature of silicon. Around the house for new applications it is super; the silicon means dirt won't stick to it and water will bead off of it, but, those same properties mean that it doesn't like to stick to even itself for a reapplication.

That's why you'll find that most manufacturers don't use it and the "best" RV sealants (Eternabond and its cousins) are not a silicon based sealant.

Good write up, with the exception of the type of sealant I would recommend...

shadow · 10-02-2013, 03:16 PM

very true comment about silicon based caulk, you'll find the same is true in the boating world, non-silicones are most prevalent as they can take the movements and vibrations stay flexible and not lose the seal

LG · 10-03-2013, 07:14 AM

I've used silicone in a few different applications and have had good luck with it. I don't anticipate needing to do more than a cursory touch up going forward unless I take the trailer apart again. A bunch of internet research makes me think the distinction between butyl and silicone is less important than just keeping the thing sealed but, going forward, if I ever need to redo it I'd be inclined to take y'all's advice on it.

I've heard people complaining about RV Cruiser and how leaky their trailers are and I've also seen some videos of some really grotesque caulk jobs so I wanted to share a few tips on how I try to keep it neat to show that it's not hard to keep it up and have it look good too.

There's a pretty good write-up here also:
http://www.oldhousejournal.com/the_s.../magazine/1417

LG.