Have a couple of windows on my new trailer that are leaking under heavy rain conditions. I found the manufacturer sealed some of the windows all the way around however most only have caulking along the top. I want to go around and seal the rest all the way around and am looking for a good sealant to use. Is there any reason we shouldn't use a standard household window/door sealant that you can pick up at HD/Lowes vs the overprices RV specific stuff?

Yes, there is a reason to use the correct product. It has to withstand the constant flexing that an RV goes through. A house doesn't flex that much so home type sealants work fine in that application. Also, those type sealants won't stick as well to aluminum or fiberglass as I found out! Use a product like ProFlex and do it once!

If you go cheap you will not be happy with the results. Use Proflex found at RV places and you will be happier with the results! I used Proflex 'clear' around the windows of my Laredo and totally solved the leaking problems. However... I caution you about sealing the bottom of the windows. You need to leave small strips to drain any water that does get in... either from outside or from interior condensation around the frames.

Your tt will get a lot more aging than the for at a stick houseThere is more expansion and contraction with temperature changesRoad vibration etc...I never had much luck with Dap and similar home productsHowever a good grade of polyurethane sealant will work just as well as the name brand RV stuffIt's the same chemical compositionI buy 3M Marine grade polyurethane at Orchard..or buy regular roofing polyurethane at home depotIt's super sticky..does not Set Up as fast as silicone ..But doesn't dry out like silicone .. and it stretches with weather conditionsBuy Dicor RV..or 3M. Etc... But stay away from the cheap home products

OK thanks for the heads up. I have a tube of DAP at home that states it is flexible so was considering using it. I guess I'll go ahead and pick up the RV specific stuff.

IMO a lot of different ways to seal a window and different types. And when one person says "sealant" or "caulking" that means different things to different people. But obviously the manufacture didn't do a good job. If you're just going to run a bead of whatever around window you'll be doing it again and again and hoping you don't have any leaks when your done.By the time you take a window out, clean up the old stuff, put on new putty tape and re-install, why cheap out on material? I do put silicon around mine but it is just a small bead or a ribbon hardly visible, and it works as an umbrella for the putty tape to help the rain along. And that also comes in handy in about 3 years because you can see where silicon starts to fall apart. And time for good re-inspection. Several RV's ago I put a little square of the brand name "tacky tape" on a fence post. I'm real impressed with the stuff. It is still pliable, I can still mash my thumbnail into it. It didn't harden and crack like the cheap stuff does. I think it has been on top fence post for over 10 years now.There's a reason some caulking sells for $1.99 a tube at and others are $12.00 Of course you could buy some O'Henrys roof patch and slap it on and by end of next summer have gobs of black streaks running down your RV. But you can get a gallon pretty cheap for what it does.Your in Nor CAl, ask your RV place if they use NWP (Northwest Trailer Parts or Keystone) If so, have them look up NWP part number 13-0865 or 13-0866 or 13-0867 Price is 8.59- 15.39 a roll depending on width and length. Very pleased with the stuff.I hope Santa brings me a Go-pro camera this year. First vid I want to make a vid about RV windows. There are some youtube vids but nothing start to finish and what to watch out for.And of course you can always believe a product works good as manufacture says it does:B Anyways I'm pleased with the stuff for windows. Other joints I use other sealants or caulking. Depends on material being joined together.http://tacky-tape.com/products/butyl-sealants/sm5227/

Good window sealant | Good Sam Community

Pirate1
Explorer
Dec 06, 2014
Clay L wrote:
beemerphile1 wrote:
The only way to correctly seal your windows is to remove and reinstall them. The caulk on the top of an RV window is mostly for cosmetic purposes plus a little extra safety. The real seal is butyl or putty tape that is used during installation. Butyl is better but more difficult to work with.

Yes.
I used a butyl putty tape like Winnebago used. Note this is not regular putty tape but is black and stretchy.
The windows were not that hard to remove. A few screws on the inside and they came out pretty easy.
x2 what he said. Make sure to get the black stretchy butyl stuff and not the white putty type. Once you reseal the windows with that stuff you won't need to mess with them again.
stevenal
Nomad II
Dec 08, 2014
I just re-did the dining area window that had been leaking. I found: 1) The window was sitting at the bottom of an over-sized hole. 2) It was installed with a foam gasket, no putty. 3) The trim screws were too long so they bottomed out prior to pulling tight.

I shimmed the opening to get more sealing area, used butyl tape in place of the gasket, and reinstalled with shorter screws. So far it's staying nice and dry while parked in the garage.
drsteve
Explorer
Dec 09, 2014
Trailer is only a month old, and the windows leak??? Back to the dealer with that one. You may already have water in the wall cavity, a future problem waiting to happen. Make them fix it, so it's documented, and they can't tell you at some later date that it was YOUR amateur fix that caused the problem.

I wouldn't lay a finger on it, myself.
ksg5000
Explorer
Dec 13, 2014
I'd take it back to the dealer and ask him to remove and repair rather than add some caulk at the top. Also - sometimes what appears to be a window issue can be a roof issue where water is entering from up top and exiting on the top of the window frame.
N-Trouble
Explorer
Dec 23, 2014
Is this the "black" tape you guys are referring to? http://www.rvwholesalers.com/catalog/butyl-rubber-tape-3-16-x-1-black.html

Its better than the white/gray "putty" tape?
beemerphile1
Explorer
Dec 23, 2014
yes and yes it is better

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