window sealant

"ottersea"....."Pirate" posted a good photo of the difference between the butyl tape and rolled caulking. Rolled caulking was the standard years ago, but always oozed, got dirty and look like heck. The black butyl is now the standard. I single layer will work fine. I would install the tape carefully on the window frame and then insert the window back into the opening. When you reinstall the interior frame, tighten it incrementally in an "X" pattern so you don't squeeze down one side all at once.

Once you're done, get some pure silicone (clear) in a tube and run a bead along the top of the window and down both sides about 6". Make sure the surface is clean.

Then caulk where the window meets the wall.

Butyl Tape. It will not oooze out if you use the correct butyl tape. The parts places sell white caulk tape and call it butyl tape. IMO, the only true butyl tape is black rubbery stuff and will only ooze out so far and then it stays in place forever. The white stuff will go bad in couple of years. My RV windows, thanks for Four Winds, used only useless putty tape. To fix all the leaks, I needed to remove all the windows and use butyl tape.

Butyl tape:


Not butyl tape:

The surface is not so much uneven as there is a a couple of ridges in the window frame. Maybe they are there to help hold the sealant I do not know. I was just wondering if those ridges, which about .020 high would make that much difference in sealing.

Butyl Tape is what is used by many(most?) manufacturers. It will squeeze out slightly but it does the job. Unless the surface is really uneven I would think that 1/8 inch thick would work fine.

I don't believe the butyl tape is going to do what you want. It will keep oozing out, and with the movement of the glass in the mounting area, you will end up with voids that will leak, because the tape never sets up. I would call a glass company and explain what you have, and what you are trying to do, and get their opinion on what to do for a lasting seal.

Kind of late to bring up but finally getting around to resealing the windows. Got them out and cleaned. Got some butal seal. My question is the seal tape is 1/8 x3/4. 1/8" thick tape does not seem to be thick enough to do the job. Is that thick enough or should I double the butal seal tape. I would hate to get it all together and then have to pull it out again since it was a chore getting the old seal off. Thanks

ottersea wrote:
Donn0128 that sounds good except it looks like ours fits in the opposite way. It looks like the frame that bolts to the window is on the inside not the outside. Don't know if that would make any difference tho.

Yes, that's the way they work. Window mounts outside, cinch ring is inside and basically sandwiches the body between the two halves of the window assembly.

Donn0128 that sounds good except it looks like ours fits in the opposite way. It looks like the frame that bolts to the window is on the inside not the outside. Don't know if that would make any difference tho.

Go to the RV parts house and buy yourself a roll of butyl putty tape. The stuff is cheap and a roll will last you nearly for ever. Take the window out, clean everything and apply the putty tape around the frame where it contacts the body. Push the window in place and while someone is holding it from the outside go inside and reinstall the cinch ring. Finish the project with a bead of Dicor around the top and two sides. Just like a residential window install.