Insulating a Van?

One thing van-hedz and #vanlife folk will find with 100% certainty is....

Van insulation is the SINGLE MOST debated issue amongst this crowd. Check any forum; Sprinter-forum.com, promasterforum.com, and others.

You'll find other issues largely sussed out (heating with Espar/Rixen, 12v wiring, etc). But opinions on insulation vary wildly.
However there are some key points. I recently came across a great post summarizing things, Ill try to dig it up.

Alex Bury wrote:Van insulation is the SINGLE MOST debated issue amongst this crowd.

This is true. I started with reflectix when I insulated my van as people suggested it as an additional vapor barrier to keep moisture off the walls when you're sleeping in the van. If you kick through the camper van forums, you'll hit information overload. I would suggest going to home depot or Lowe's, looking at foam board, reflectix, and any other insulation, and seeing what makes sense to you. A lot of building my van was a certain degree of experimentation despite a lot of reading on the topic...

Eli Peterson wrote:. For it to be efficient though you really need some space for air.

It doesent appear you have any space for air between your panels and the insulation. Did you not just attach the insulation directly to the body of the vehicle as it appears in the photos? How did you do it?

It also seems like one of the easiest ways to keep the van cool is to add a roof vent. Even if the fan is off, if the vent is simply open it will let hot air out, no? Since this is a cargo van, I have considered that maybe a vent fan actually might not reduce the resale value of the vehicle as it's designed for work purposes anyway. Maybe that's the one mod I can add that would be okay.

I insulated my van with 1" foam board from Home Depot. I cut it to width so that it was a press-fit between the structural ribs of the van (walls and roof). I then covered all the surfaces (wall, roof, floor) with "Low-E" insulation which is much better than Reflectix. I took all the scraps of Low-E from cutting sheets and stuffed that into the hollow ribs and voids. Finally added 1/8" wood paneling over everything. Worked well, kept the heat out until about noon. No condensation appeared on the exterior in the morning, so I think I did a pretty good job attaining 100% coverage.

Regarding attachment - I would look at gaffer tape. Used in the film/photo industry as it doesn't leave any gummy residue, even after months of attachment. No idea what it will be like after several years though.

Yes mine is connected directly to the walls (stapled into the wood). There just needs to be air on one side, I have built small cabinets on the inside so that there is 3.5 (one 2x4) inches air between the insulation and anything else

I realize this is an old thread, but I'm reviving because I'm doing my own van conversion research..

The idea of using the 3M Thinsulate got me thinking. Couldn't you do velcro and put felt against the exterior wall (in the cavities and such), then put the Reflectix, then a layer of foam board, then wood/whatever.

If permanence isn't an issue, spray adhesive, felt, Reflectix, foam board, etc.

Does anyone see an issue with that? You'd accomplish having a very lightweight, porous barrier to provide that air cushion between the Reflectix and the metal.

I like “Fomular” rigid foam boards. They are pink and you can get them at Home Depot. You can cut them cleanly without a hot knife, which isn't true of many other foam boards. Just score and snap. In my experience, all of the tapes eventually fail. Because the van is such a small space, you want to minimize materials that off gas. Insulation can help in hot sunny climates. With a good solar powered fan set up (one bringing air in and another on the other end pushing it out) and an external covering over the windshield, I can keep my van just below the temp in the shade through long AZ days, even when its parked in the sun. That can still be hot, but nothing like the way temps can skyrocket in vehicles with a lot of glass.

Jen Tuuli wrote:I realize this is an old thread, but I'm reviving because I'm doing my own van conversion research.. The idea of using the 3M Thinsulate got me thinking. Couldn't you do velcro and put felt against the exterior wall (in the cavities and such), then put the Reflectix, then a layer of foam board, then wood/whatever. If permanence isn't an issue, spray adhesive, felt, Reflectix, foam board, etc. Does anyone see an issue with that? You'd accomplish having a very lightweight, porous barrier to provide that air cushion between the Reflectix and the metal.

The adhesive used on the backside of the Velcro is not going to like being baked at 150F all day, which is what it will probably see paired against bare sheet metal sitting in the direct sun. I could be wrong though.