Your FRP construction has glass laminated to each side of a wooden core. The wood has a R value of aprox 2.5 per inch, so it will be an effective insulator, keeping the warm inside air from touching the cool outside environment. This should eliminate any condensation. If you don't have this problem now, you won't later. The fiberglass construction is also an effective vapor barrier.

You concern should be in how you plan to attach your paneling to the fiberglass, mechanically or with adhesives.

Gard

Gard to answer your PM, I think the walls are about an inch thick or so.

I was thinking about attaching with adhesive..? Good idea or not?

Stef,

I dropped a note into your inbox.

RTSmith

www.SelectTrailer.com

I'm not sure how your panels were manufactured. Some layups involve a wax added to the resin, to allow it to harden and cure. This will be found on the surface of the fiberglass. If it is present, it would interfere with the bonding strength of an adhesive.

To remove it from large areas would be time consuming and somewhat difficult. It would have to be wiped with a solvent and sanded to present a better bonding surface. The solvent used in FRP layups is very noxious, and when used in a confined area, necessitates the usage of a chemical respirator.

Since you have an inch of solid material in which you can affix fasteners, it might be easier to install furring strips with screws. You can then easily pin nail and glue the individual paneling to the strips. Having the 3/4" available space, will allow you to run wiring and plumbing if you needed to.

Since you will be screwing wood to wood and fiberglass, you won't have the usual problems of galvanic reaction with different metals. This is often a problem with after market installations in aluminum trailers.

Gard

Steff

Are the walls of your trailer smooth like a counter top, or rough in that you can see and feel a fabric weave? You can perform a simple test to determine if gluing the furring strips would work.

Choose an area that will be eventually be covered, and by using some polyurethane construction adhesive, try gluing a block of wood to the panel. After the glue has cured, and if the bond is good, you should have difficulty knocking the block off the wall with a hammer. In fact, the glued joint is usually stronger than the wood itself, particularly when using a pine/spruce strip.

If the wood just pops off easily, then the surface will have to be prepped if you wish to glue the furring strips to the wall. In this instance, I would then again suggest a mechanical attachment of the wood to the walls.

Gard