Replacing front overhang window in 2009 Class C

You are right to assume problems. If you have had water, you could have dry rot. That robs structural strength. Or you can have wet rot, and sealing it in is even worse. If you have had water around the window, water settles to the lowest point, so it could creep to the bottom of the overhang, then it flows to the overhang corner and down.. Don't ask me how I know this. Usually, if you have noticed water on the inside, it's a lot worse than just a local problem.

The framing varies from brand to brand. Usually there'd be a wood or metal ring, at least, and hopefully tied into the rest of the cabover structure (and not just floating, surrounded by styrofoam). Water damage would tend to occur first to the luan skin around the opening, inside and/or outside. If the framework is aluminum, it's obviously not going to be affected by water; and neither is the styrofoam core of the wall. You're also somewhat likely to have damage to the bottom part of the front of the cabover, where the bunk board meets the front end, and whatever structure is there since gravity will make the water collect there until it eventually finds a way out.

Removing the window unit is indeed pretty straightforward, but rather awkward without help and scaffolding. You take out the plethora of screws that hold the compression ring to the window frame, take the ring away, and pull the window unit out, possibly after trimming off any caulking or other sealant holding it in place.

Personally, this is a job that I would take to a repair shop if there's a decent one around as they'd likely have the help and the staging ready at hand. I similarly am happy to pay other people to do exhaust system work on my vehicles when needed, even though I could do it myself, as the money involved seems a bargain compared to the frustration of rusted together bolts and junk falling in my face as I scrunch around on my back.

I tackled that job once and it was not too bad, but I didn't have any damage. It's worth it I think for a look see. You can always put it back in and hold it in with several screws and take it too a pro. Use a drill and proper bit and undo all the screws. The window won't fall out. You have to pull the frame away from the old caulking. Gently go at it from one corner and pull it away from the body and the caulk will yield. Once it's out you'll know your situation. For me it was as simple as running some new caulk around the outside, then fit it back in and screw it down.

Thank you for the comments.
I have also thought about just pulling the window and covering the opening. Has anyone done that to their rig?

Another thing to consider might be to put a good thick piece of pexi-glass on the outside over the entire window opening. Take your rig to a plastics place and see what they think of that. They would know what sealant to use, and if it needs to have a built up edge they could put it together for you.

I have never pulled a window in an RV but I have done some extensive repair on old wooden boats year ago. I would cut the caulk around the window with a razor and remove it being very careful to not damage the frame. Inspect the plywood inside the frame area and if you have an inspection camera you could thread it down between the inside and outside wall to look for mold or rot. If you dont have one pick one up on Amozon that connects to your laptop USB port for $15-$20. If you have a sheltered place leave a fan blowing in the cavity to dry it out. If you see rot down inside take it to a pro. If you just have some bad wood near the frame get a product called Git-Rot. You inject it into the wood and it hardens stronger than the original wood and is impervious to water. Of course reinstalling the original window is the easiest option but you could have a fibreglass man patch the hole but expect a bill in the thousands for color matching gel coat and forming the fibreglass to look seamless.

Artum Snowbird wrote:
Another thing to consider might be to put a good thick piece of pexi-glass on the outside over the entire window opening. Take your rig to a plastics place and see what they think of that. They would know what sealant to use, and if it needs to have a built up edge they could put it together for you.

I had not thought of this. The only thing I would have to do is to build some a frame to cover the opening between the plexiglass and the wood interior. Interesting idea, thanks.

samven1 wrote:
I have never pulled a window in an RV but I have done some extensive repair on old wooden boats year ago. I would cut the caulk around the window with a razor and remove it being very careful to not damage the frame. Inspect the plywood inside the frame area and if you have an inspection camera you could thread it down between the inside and outside wall to look for mold or rot. If you dont have one pick one up on Amozon that connects to your laptop USB port for $15-$20. If you have a sheltered place leave a fan blowing in the cavity to dry it out. If you see rot down inside take it to a pro. If you just have some bad wood near the frame get a product called Git-Rot. You inject it into the wood and it hardens stronger than the original wood and is impervious to water. Of course reinstalling the original window is the easiest option but you could have a fibreglass man patch the hole but expect a bill in the thousands for color matching gel coat and forming the fibreglass to look seamless.

I do have to, at some point remove the window, as parts of the wood underneath is rotten. That is my issue: how much of the wood against the front wall and around the window do I need to replace, and how to replace it. This is beginning to sound like I will need a professional who has done this before. It is not something I'm going to do quickly, that is for sure. Thanks for the idea.

This company has some great videos on repair. https://www.youtube.com/channel/UCTM63S5mql7mcZ312UcI75w