So, correct me if I'm wrong, but I could use the same fiberglassing technique with foam and say 1/2 or 2/2 wood construction to build the various pieces of the 'furniture in the PP? i.e. The seating for the dinette area? Kitchen cabinet front? Closet sides and shelves? Would the wood/foam strutures also work with fiberglass sheets? Lowes has 4/8 sheets in both white and ivory. Thought about it for the walls. Foam and fiberglass panels would be so much lighter to work with and would provide a better method for fine tuning the fit to the interior walls. Now I have a whole 'nother thing to think about.
Fiberglass over foam seating:
Dunno... The structural issue is the key one of course - don't know if it could take the weight
. Probably depends on how thick you lay the glass up. Glassing both sides would be a lot stronger than just the side that shows.
Fiberglass sheets at the big-box stores:
That's not fiberglass reinforced resin (what the trailers are made from), but is Fiberglass reinforced plastic (Kinda like the stuff the put on stick-built trailers they call 'fiberglass'). I used that to repair the HUGE hole that was in the closet of my Boler
. I ended up basically sheathing the old closet with FRP, using the original glass for structural support and the FRP for looks. It's really surprisingly tough stuff. Some have expressed concern about using it for outdoor applications since it's not UV protected. Course, I've got a sheet of the stuff sitting in a north facing door that gets 24/7 exposure for the last 2 or 3 years. I suppose I could check it.
For either of these, it should be easy enough to mock-up a quick seat using both methods and test them to see how they hold up. For the seating in my PlayPac, I framed it up with 2x3s (overkill) and covered with 1/2inch plywood.
If you decide to try the FRP sheets - get the matching trim pieces for corners and edges. (Actually, for the curved corner edges, I just covered it with white caulk - looked great!) You might think the FRP panels would take a 90 degree corner well with a little heating - but I wasn't able to get it to go. I used a heat gun to soften the area I wanted to bend. Darn thing just kept wanting to spring back to it's normal flat state. I might have made it TAKE the corner when hot - but it wouldn't retain the shape like I was asking it to do. That was 5 years ago though so my memory might be fading on that one.