Newbie here. Glad to find you guys and gals.
As I plan my build, one of the topics I have agonized the most about is wall paneling. Let me tee this up: this will be a high-end build. 36' gooseneck/28' floor, 8.5' wide. All-aluminum frame Sundowner. I STRICTLY FORBID any wood or paper construction materials to hopefully keep mold/mildew at bay. Interior cabinetry will also be aluminum. So wall paneling has been a real head-scratcher for me. Honeycomb composite? Lightweight and rigid but astronomically expensive. I'll spare you all my agony.
Then a few days ago I found some scrap plastic at a plastic machine shop and was amazed at how lightweight it was for its rigidity. Discovered it is called Expanded PVC foam sheet which you can get in different densities and thicknesses. Turns out to be popular in the sign-making industry. Brought some 1/2" thick stuff home, started working with it, and was blown away at its workability, machinability, etc. For example, I drilled a wood screw into the very corner without countersinking first and it did not split out! Couldn't believe it! Turns out there are some other benefits such as good self-extinguishing fire resistance, moisture and chemical resistance, FDA compliant for kitchens, etc. Not UV stable so not ideal for outdoor use.
Anyway, just wondering if anyone has experience with Expanded PVC sheet as a wall-paneling application? Painting it? Does wall paper stay stuck? How do you deal with seams? How does it stand up to high wall temps in the summer? My thermal bridge furring strips will be the same material just thicker.