Found a trick for insulating container walls without losing space

I was about to frame out my container walls with 2x4s but then a builder in Phoenix told me to try spray foam right against the corrugated metal, it fills every gap and I kept all my interior width. Has anyone else used closed cell foam on their build and did it hold up over a few summers?

2 comments

2 Comments

barbara42915d ago

Respectfully, I gotta push back on that a little. That spray foam against the metal can trap moisture between the foam and the corrugated walls, which leads to rust over time especially in humid climates. I have seen a few builds where people had to rip it all out after a couple years because the metal started corroding underneath. It is a good idea to leave a small air gap or use a vapor barrier between the foam and the container walls to let things breathe.

casey_campbell15d ago

Whoa, hold on a second there. I gotta say you're mostly right about the moisture thing, but that vapor barrier idea can actually make things worse if you're not careful. The problem is, if you put a plastic vapor barrier against the metal and then foam over it, you've just created a perfect little sandwich where water can still get trapped between the steel and the plastic. I've seen guys do that and end up with rust spots right where the barrier meets the metal seams. Best way I've found is to use a closed-cell spray foam that bonds directly to the metal, then make sure you've got good ventilation on the inside to let any moisture that does sneak in dry out over time. Still, you're totally right that in a humid climate you gotta be extra careful no matter what you do.