Spray foam insulation

[frthompson]

Anyone apply spray foam insulation to the underside of your floor to insulate it? I've seen concerns expressed that spraying against metal frame members could hold moisture against the metal and cause rust. But what if you just sprayed the underside of the of the plywood? There are DIY spray foam kits available now. I guess an alternative to insulate the floor is to glue on pieces of foam insulation board?

[FRED SMAILES]

I have no experience with the idea but imo if you sealed the metal from moisture first the foam would be no different than paint applied to metal. Would the foam stay stuck would be a question

[Jon Vermilye]

This is an option with Escape trailers. The pros - warmer floors and better cooling in hot summers. Cons - Makes repairs under the trailer difficult.

I used Locktite PL Premium Max or better but harder to find Loctite PL Premium FAST GRAB Polyurethane Construction Adhesive to attach 2" blue board Styrofoam to the undersides of my trailer. Painted it black. Much neater, and makes repairs to plumbing, etc easier. The advantage of the Locktite products listed is they do not "eat" Styrofoam, and they cure without air, important when gluing foam to fiberglass.