Teardrops n Tiny Travel Trailers

The next chapter in my ToyBox build is being outlined: Insulation

I've got a stock of spray foam to fill the hollow extrusions and the hat channels in the roof.

The walls are FRP so this should be quite easy. My plan is to use Z or hat channel metal furring strips. They'll line up with the roof channels.

Since the walls are strong is there any need to use hat channel? It would mean cutting strips of foam to fill the void in order to break the thermal bridge.

3M VHB has been recommended for many uses. There are several versions of the stuff. What experience do you have with any of them?

http://www.uline.com/Grp_240/3M-VHB-Tapes

Can you recommend one over another for attaching the channels to the FRP?

What about attaching the foam to the ceiling/walls? Would spray adhesive be a better choice?

Thanks,

Tom

Spoke with some engineers over at 3M and they said definitely don't rely on VHB (any variant) to hold to the foam. They also couldn't think of any other 3M tape products that would work for that purpose. Rather disappointing. Haven't found any other tape alternatives yet, but I'm not giving up hope. Tape just seems so much less messy and annoying vs gorilla glue.

Steve,

Do you have contact info for the 3M engineers? I'd like to know what limitations to expect.

The foam is going to have its edges trapped by channel. Then there will be some sort of paneling on the inside. The tape would just hold it in place and not be 'structural' so to speak.

I'm wondering about using tape to hold the Z or hat channel to the FRP instead of screws. Fewer holes means less chance of water getting where it shouldn't be and getting rot going.

Tom

Unfortunately, no I don't. I called from their website and got bumped around from one unknowledgeable person to another until I finally was forwarded to the engineering dept. Spoke with a couple fellows there for about half an hour until I ran out of questions and they ran out of new ideas.

If it is just holding the pieces in place and is not structural, I think you could use ... ah crud, I can't find my notes. There was one of the VHB tape families that we discussed using for the foam in the nonstructural parts of my build. They suggested that one for sealing/waterproofing the joints. I'll see if I can find my notes.

How about the 3M Fastbond series of contact ahesives?

3M Fastbond Brouchure