Teardrops n Tiny Travel Trailers

Ok been spending the last two days looking at ideas and trying to find some info, these questions may have been asked but I am going to list them and if anyone has answers or experience with this let me know.
1. How much "advantage" is there to insulated sidewalls verses 3/4 plywood side walls?
2. If you coat plywood with expoxy resin what is the length of weather durability if must leave your TD outside for extented periods also if you epoxy coat it how well will it paint if I decise I don't want woodgrain?
3. If you coat masonite/hardboard with the same is the life the same or less than plywood.
4. And I couldn't find this one has anyone used galvinized sheet steel for an outerskin verses aluminum also how about pre-painted steel?. I know more weight.
5. I see in pictures lots of wood sides with covered tops are these mostly aluminum or somthing else?
I have just been thinking some of this over and wondering if there are some things about all of these pro/con that I am missing

MRW hopefully here's a couple of answers to your questions.

1. whether or not there is an advantage to insulating or not is kinda up to you and how you can adapt to different temps and how you camp. Doing a lot of winter camping...build an insulated one. I think you'll find that a tear is more challenging to heat up than cool down. I have solid ply sides, but an insulated ceiling. In hot weather I can run the Fantastic Fan and it is comfortable enough for me to sleep at night. Midwest temps and humidity in July...Death Valley in August..probably not. At 28 degrees with a dog in there with me, it was comfortable at night.

2. For coating plywood. Others may disagree with me on this but in the boat building industry, especially for custom wood boats, epoxy is what is primarily used. Some of the old school restos still use varnish...however, without some sort of cover they require nearly semi-annual maintenance to keep them in top notch shape. It is done mostly to be authentic with the restoration. Depending on the show, you can lose points if it's an epoxy constructed boat. Epoxy does need to have some sort of UV protective top coat. Auto clear, varnish, urethane whatever.

Wood does breathe however, and you shouldn't wrap it in heat shrink like a plastic boat for winter. Ideally some sort of tarp with an air gap at minimum would be recommended. You can paint right over the epoxy if you want a colored one. Any tear left outside is going to take more maintenance than one that has some sort of cover to keep it looking good.

3. Masonite and hardboard while used in tear building years ago probably isn't your best bet. Others may disagree. It won't take much water penetration for it to deteriorate. Ply is a much better choice. If it does get wet, the ply in the wood will still hold a screw, not turn mushy. You can get an exterior rated ply or upgrade to a marine grade ply, (solid laminated layers) with an antifungicidal glue.

4. I have no idea............

5. I used aluminum on the roof on both of my woodies. It works pretty easily and will bend to the curves you want and won't rust if you get a ding in the paint. Others have done vinyl tops, wood strips, filon, pre painted steel, even some in canvas. Whatever works for ease and $$ for you.

This is just my opinion, others may vary. Doug