Help! Our windows hate us!

[SarahEllie]

Hi,

I have a flat nose 2001 International Amtran. We knew that there would be issues but the windows have been kicking our butts.

We started by taking all the windows out, cleaning off the old seal and then washing the windows.

Then we replaced the windows with 3M dynatron 550 and new weather foam strip across the top. We made sure to go thicker in the bottom corners because of the gaps.

However, we noticed that it wasn't drying, at all. So we removed that and decided to turn to butyl tape.

We used butyl tape the exact way that we saw in some videos on YouTube, on the base on the windows and up the sides of the windows. But we did double up on the sides because we noticed that there was a huge gap between the window and the frame. The double up closed the gap but we still had an issue.

The butyl tape was very noticeable from the outside and our windows stuck when we opened them. We then went to every window and tried to remove the visible butyl tape. Unfortunately, it leaked when we tested it.

So we decided to start again.

This time we used a mixture of butyl tape and sikaflex 221. We did the same thing with the butyl tape but this time we put a bead of sikaflex on the sides of the frame as well. When the window were in, we went outside and smoothed the sikaflex. Even though they were VERY well covered, they were still leaking when we tested them.

So we decided to go a path we didn't want to go, silicone. We also decided to weld the corners of the windows to close the huge gaps we saw. Then we watched another video, followed their technique exactly, only putting in 6 windows. And once it was cured, a big rain came. Three out of six were leaking.

We honestly couldn't understand how the water was getting in, so we just stopped working on the windows for a while and moved on to other projects.

Now we are back to the windows, but it's not getting any better.

This time we tried a foam weather strip across the top, rubber weather strip down the sides, butyl tape across the bottom, sikaflex on the outside, and Great Stuff foam on the outside corners. We thought, this is it, we did it!

We only did four windows like this. Three of the windows are leaking. Two of the windows are leaking from an area we can't find, and all three of them have leaks coming from the seal that holds the glass in.

Please help! We don't want to keep throwing money at these windows if nothing we do will work! We are posting a lot of stuff on Instagram (PolyPhoenixFamily, if you want to see what we've done so far) about it, but if you need pictures or anything just let me know.

[Bus'n it]

Sorry for your window woes. My bus windows were pretty much shot so we decided to just go with dual pane RV windows. I don't have an answer for you but curious why the seal didn't dry. Is it cold where you are at?

[SarahEllie]

We were confused about that too! We live in Florida so it definitely isn't cold here and as much as we get rain, it wasn't rainy during that time. The Dynatron that was on the outside did dry in some areas but not all and when we took one of the windows out it was all wet like we had just put it on. We could not understand what happened with that one.

[Drew Bru]

We felt the almost same pain with our Amtran, but we found the problem before we removed the windows for a 3rd time. We eventually threw in the towel, out of frustration, and put in an internal gutter system below our windows. This works fairly well for any seepage or condensation runoff but we did eventually find the source of the leak. In our case, the water was seeping in through the cracked/dry-rotted seal at the bottom edge of the glass (where it meets the aluminum frame). Water would get through those micro cracks and migrate into the metal frame (it's a channel) then it would flow to the corners of the frame and dump into the bus.
Our proof-of-concept solution was to put weather sealing tape over that gasket, and it totally worked. We kept it that way for a year before finally getting around to smearing that gasket with a bead of clear seam sealer.

[SarahEllie]

It's such a relief to hear that we aren't alone with these windows.

We have noticed the leak at the gasket and we know we need fix this but we don't really know how. We tried Flex Seal, but it definitely still leaks through.

We will have to try the weather seal tape or the seam sealer to fix that.

[musigenesis]

When I removed all of my windows to clean them before reinstallation, I noticed that the corners of these windows (where the bottom piece of framing meets the two horizontal pieces) had very thin gaps that allowed water through (it actually sprayed through when I put the hose on it). Because of how these windows sit in the bus frame, any water that gets in through these window gaps gets into the inside of the bus. Generally, this will only happen if the bus is not sitting completely flat; when my bus is parked facing a bit downhill, water can pool on one side of the window sill and cause this leaking.

So I've been trying (not entirely successfully) to seal these corners up with Dynatron-550, by applying either with my pinky or with a small craft brush that can reach into that little gap. I can seal it and stop any leaking, but one of the issues I have is that when I fully open a window, the little stops at the bottom press down into this area I've sealed and tend to dislodge the sealant, causing it to start leaking again. I'm currently experimenting with sealing small blocks of HDPE plastic into these gaps with sealant, which gives the window foot something solid to land on.

As others have mentioned, many of my windows are also leaking past the gasket that holds the glass into to its smaller frame; a little smear of Dynatron-550 on the outside of these corners stops that.