I did that:
http://www.benplace.com/85rouge/interieur_12.jpg
http://www.benplace.com/85rouge/interieur_8.jpg
in m'y van and a few other van, and that (call Resisto)

http://www.benplace.com/83westy/blanche116.jpg
http://www.benplace.com/83westy/blanche126.jpg
http://www.benplace.com/84westy/blanche150.jpg

In a few other vans (folks who like to camp in winter)

and the bubble stuff is NOT GLUED to the wall,  BAD IDEA if you live up
north or in humid/salty area!!! again, you may trap humidity/water/salt in
between the metal wall and the insulation.

If you live in a dry and hot area, that is another story. That bubble stuff
also help for sound proofing.

Ben