Insulation…ah the question that gets so many varying opinions when building out a van. Foam? Wool? Denim? Pink stuff? Thinsulate? Vapor barrier? There are so many variables when insulating a van that it is pretty much impossible to fully insulate it. For this reason and also that our van was going to be used mainly for 3 seasons with a hint of winter skiing excursions, we went with the following techniques/products:
The ceiling and walls/cavities were first covered with noise deadening material. Its basically a butyl tape product with a thin aluminum covering that you roll onto a surface. This is a MUST IMO. It definitely kills the sounds in the van and does help to plug up any holes in the van floor.
Next, we used 3M 90 adhesive spray to apply our Thinsulate insulation to the ceiling and walls. We chose Thinsulate because we liked that it was non-toxic, had a good R-value and had good non-water absorption properties. Sure, its a little more expensive but there was no way I was going to risk pink stuff/fiberglass in such close quarters nor was I going to splurge on a product like Havelock Wool or Denim.
For the flooring insulation, we choose to use XPS foam sheets available from your local hardware store. They are easy to cut and can be applied to your subfloor with the correct adhesive (meant specifically for foam applications).
