Repairing water damage

[Littlebirch]

Hi All - Recently purchased a 1993 Ultra limited edition. We came into this knowing that it would need some work on some water damaged panels by the dinette and couch. As we started removing the luan and plywood behind the driver’s seat, we followed the damage up to the cabover. It rotted all of the luan between the fiberglass bottom of the cabover and the metal frame. It looks like the leaking is coming from the front portion of the roof (Major amounts of slathered caulking) and that will be addressed. We are older and want to get camping! We don’t want this to turn into a major project (more than it already has!) but want to be safe. Would we be ok with just putting spacers of luan in between the fiberglass and metal framing, or do we need to replace all of the luan? We won’t be using the cabover for sleeping, just storage. Thanks for any suggestions

[RVJeff]

Hi, I have an older class A and previously owned a travel trailer with similar damage, never had a class C so maybe someone with more knowledge will jump in. But in the trailer, the fiberglass was glued to a panel of luan and Styrofoam insulation. Not sure if that's what you found here. Am I seeing daylight between the floor and wall of the cabover? Is this just the fiberglass skin that's pulled away from frame? I would want to first make sure bottom fiberglass is well attached to metal frame. Good cleaning followed by construction adhesive between the two (I've used liquid nails fuze-it weatherproof with good results), maybe supplement with a few pan head stainless sheet metal screws into pre drilled holes. Might then use some brush on epoxy to strengthen any residual luan adhered to the inside fiberglass. Might want to get some insulation board same thickness as metal frame to sit inside those spans between the metal frame members. On top of the frame I'd use something more substantial than luan. 3/8 plywood at least. Maybe some angle bracket also to tie together the floor and sides for good measure. Again construction adhesive and a few stainless screws. Seal everything up on the exterior with a good RV caulk like geoflex. Dicor products on the roof. Good luck!

[Littlebirch]

Thanks, Jeff. Yes, the daylight that you see is the fiberglass dropped down after we removed the trim pieces. We ended up dropping down the whole fiberglass panel and removed all of the insulation and luan. The lower aluminum frame was racked so we put 1/8” plywood between it and the upper frame, then pushed it from the passenger side to realign it with the upper frame and secured it with screws. We slid in a new piece of luan below the frame, using adhesive to affix it to the aluminum frame. Then we used Locktite marine adhesive to affix the fiberglass panel to the luan, using a linoleum roller to give it a smooth fit. On the inside, we put new 1” insulation in the spaces between the aluminum frame and topped it with 3/8” plywood. We’re closing in on sealing up the roof, replacing the front running lights and using new butyl tape on all of the trim. Thanks for your suggestions!

[Littlebirch]

Sorry, don’t know why two of the photos are rotated and I can’t figure out how to edit them!