I got a lesson on construction for 2012 passport trailer they use cardboard between outer walls of the inner walls so basically if you have a leak the cardboard sucks the water in like a sponge why th...
If they don't use Styrofoam, whatever they put between the walls probably will absorb water. I have a Passport by Cobra, don't know what they used in mine, but the key is to try and keep maintenance up so they don't leak. Brian