Repair Delaminated Pannels, Is it possible? Options

[ddbradley952]

I have a fiberglass exterior Winnebago Minnie-Winnie with delaminated wall panels.

The construction (Laminated panels) process is where the inside panelling is glued to the Styrofoam core and then an exterior layer of wood panelling is glued to the Styrofoam core and then the fiberglass shell is then glued to the outer wood panel to make one very solid panel much like plywood is constructed. they all support one another for strength. Precise metal strips are inserted between the layers where ever interior furniture is scheduled to be screwed into the wall. That's how Winnebago does it, Fleet-wood does something very similar I think

The downside is that if you ever get moisture in between the fiberglass and the Styrofoam say from a leaky roof, window, antenna or roof-air (which does happen) you can not get the water out, it is permanently trapped and it warps and decays the wood panel layer and delaminates (separation) the fiberglass siding resulting in large sagging bubbles in your siding and unlike in a conventional home, repair seems impossible, you can not remove the siding to get to the damaged wood because it is all glued together. AAARGH!!! You don't even know you have/had water in the walls until the damage is done.

Question then, is if anybody knows how to repair or re-laminate these bubbles? can glue be injected somehow?

[RBS]

If it is like fiberglass repair on a boat it can get quite expensive if you have a good fiberglass guy. If I had a fiberglass blister that size, I would definitely take it to a good fiberglass repair shop unless you have a lot of experience working with fiberglass. If you do it yourself and are not experienced, it is hard to match the texture and the gelcoat. If it has seperated and you have a bubble, then the fiberglass is also going to have to be repaired or it will never look right. When gelcoat absorbs water, it blisters and you have to totally repair the fiberglas. Sorry Mr Bradley, IMHO there is no easy fix for the delamination problem. I know of people who have experienced this problem with boats and it was a costly repair.

I agree that "Great Stuff" exandable foam aerosol is an excellent option. My 92 Winnebago Minnie had delamination within the starboard aft panels. I removed the aluminum corner angle trim strip and opened the panels to allow the LUAN (wood laminate layers) to dry thoroughly (fans help)- I removed as much of the damaged LUAN that I could reach . Then prepared a means of applyong flat solid even pressure to the area being repaired - I used thrick aluminum plate - see asttached photo. before applying pressure drill a couple of holes in the center area being treated from the inside. Be careful not togo through the outer fiberglass skin. Take a flat blade screwdriver twisting through the foam layer to provide clear access to the delamination void area. Masking tape around holes and papers under to catch excess as foam expands. Foam is exceptionally sticky - prevention beats trying to clean up. Carefully apply foam IN HOLES - DO NOT OVER FILL AS OVER EXPANSION COULD CAUSE FURTHER PROBLEMS. Immediately apply exterior pressure so that panel is flat - allow to cure overnight.