Caulk silicone on top of butyl tape ? Yes or no

[JRC]

First time question. OK I purchased a trillium that needs work. I have read many things on this site. Very helpful.

I have removed cleaned, applied butyl tape and reinstalled 2 windows so far.
My question is this. Once I trim the tape do I put a bead of silicone on top of the butyl tape or just leave it as is.

I read so may things to stay away from silicone.

Thanks for any advise

[rbryan]

You read right. Once you apply silicone, it's extremely difficult to remove it. Nothing sticks to silicone - even more silicone. Just go with the Butyl tape. It's designed for things like sealing windows, and is easily replaced if it deteriorates. If you want to help the window seal last a bit longer, add a bead of clear ProFlex or Lexel (they're not silicone) along the top ledge only, not all the way around.

[Neto]

If you do it right you will not need to silicone.

[Donna D.]

Originally Posted by Neto

If you do it right you will not need to silicone.

Even if you do it wrong, you don't want silicone!

[JRC]

OK . Thank you for the replies. I guess I will just trim the butyl edge of the tape at a 45 degree angle.

[k0wtz]

I like silicone use it all the time!

bob

[Casita Greg]

Originally Posted by k0wtz

I like silicone use it all the time!

bob

Once it ages a bit and loses its adhesion, I'm thinking you won't like it so much down the road.

[floyd]

Originally Posted by Casita Greg

Once it ages a bit and loses its adhesion, I'm thinking you won't like it so much down the road.

I still like it after decades, how much longer 'til I don't?

[Kai in Seattle]

NO, NO, a thousand times, NO silicone!

And we used a popsicle stick end to "round" the butyl tape to a nice edge.

Nothing sharp.

BEST
Kai

[k0wtz]

while at walmarts I bought a new silicone caulk marketed by the people that make the wood glue best I have found!

bob

[Trailereva]

Hi, I have always used the RV proflex. I am sealing up my windows and would like to know why, after trimming the butyl, the recommendation is only to run a bead along the top of the window. Would it not be good to seal around the whole frame?
Thanks!

[rbryan]

Originally Posted by k0wtz

while at walmarts I bought a new silicone caulk marketed by the people that make the wood glue best I have found!

bob

Silicone's a bad idea on a fiberglass trailer. There are a number of reasons. It's been discussed ad nauseum on this forum as well as many others. Read through all the links referenced in this thread.

http://www.fiberglassrv.com/forums/s...ad.php?t=49621

If you're still loving silicone after all that, there are plenty of blogs with advice not to use it, like this one:

http://www.roadworkplay.com/2013/11/...ng-our-camper/

Or this one:

http://www.liveworkdream.com/2016/08...or-rv-sealant/

Once you realize it's extremely difficult to remove, and nothing sticks to it, silicone loses it's appeal pretty quick. But hey, knock yourself out.

[stevebaz]

If done right with the butyl tape the joint will be sealed. The only reason for any type of overcoat in the product you choose is because exposed butyl grabs dirt and wont look good over time. You cant wash the dirt out of exposed butyl tape.