I recently wrote an article for Teton Sports explaining what I would do if I could rebuild my van all over again. I have to admit, it may not be that riveting. No one really cares about insulation or furring strips. Instead you want to read that I would have put my kitchen over there or used tongue-and-groove on the ceiling or that the bed should magically rise out of the floor. You catch my drift. But sorry, van insulation is where it’s at.
I want to go over in more detail what I’ve learned over the past two years.
VanLife and Van Insulation Resources Two Years Ago
Two years ago, it’s not that long, right? No new van insulation products have really changed the game, nor has any of the old ones gone away. But there is more (and better) information today than there was 2 years ago. Back then, the only real resource for insulating a van was this Instructable link and maybe 3 or 4 other websites that all said different things. I had to do the best I could with the information I had at the time.
Using Reflectix Incorrectly
Back then, sticking Reflectix all over your walls was all the rage for van insulation (and it still is), but it was really confusing. People were using it successfully as sun reflectors in their windows and then decided to start sticking it all over their walls.
“Hey, if it reflects heat through the window, it must reflect it through my walls too.”
From an engineering standpoint, I knew that couldn’t really make sense. SunLIGHT would be reflected, but thermal energy hitting the wall would just radiate through any barrier in complete contact with that surface. I did check the manufacturer’s website (which is also kind of garbage) and they confirmed.
“For Reflectix (or any foil backed insulator) to be effective, a minimum air gap must be maintained between the heated surface and the insulator.”
Yet, all the websites and YouTube videos I found still showed people sticking it to the walls with spray-on adhesive. I followed like a sheep.
The Heat Source Location Matters
It’s not that I followed blindly without thinking, but I was still struggling with the correct way to use it, and I was in a hurry to get the whole project completed. You see, if you follow the heat source from the OUTSIDE of the van (the sun), yes, it would hit the van wall and radiate directly through to the Reflectix with no air gap. The Reflectix would then conduct most of that same heat to the inside of the van.
However, what if you followed the heat source from the inside of the van and directed it outward? There would definitely be an air gap between any heat source and the Reflectix (through the wall sheeting and fiberglass insulation). This would be extremely helpful in winter when heating the living area.
So, confused and rushed as I was, I just decided to follow along. The materials were not that expensive and I knew it wouldn’t hurt my insulation in a worst case scenario. The worst case is that I simply wasted time and money. Oh well…
My Verdict on Reflectix for insulating your van
Don’t waste your time or money.
Even with all the people jumping into VanLife and broadcasting their builds on YouTube and blogs, I still haven’t seen a great (or easy) application of Reflectix using an air gap. You would have to find a way to use 1/2″ to 3/4″ vertical furring strips to keep the Reflectix off the wall, and then attach horizontal furring strips on top of those to complete the insulation process (assuming you also decided to stick with fiberglass insulation on top).
Spray Foam Insulation
This is what I said I would re-do in the Teton Sports article.
Done professionally, the chances of bulging or deforming your walls decreases. So does the chances of you applying areas too thickly and having to worry about toxic off-gasses. The chances don’t go to zero, but they’re probably better than if you do it yourself.
The reason I chose this method is its proven R-value and performance in this exact type of installation (refrigerated trucks and semi trailers) and its resistance to water and moisture.
The cost of this quite a bit more, $200-$300 for my current install vs. $800+ for a professional spray foam installation, but it could be worth it for the longevity of your van.
The Biggest Question about Van Insulation
Here’s the problem — No two vans are completely identical. That makes it impossible to make any kind of rudimentary, scientific measurements. i.e. Two vans that are carbon copies of each other in design and components, but one with insulation and one without.
Anyone that read my other page about insulating my van knows I did it as best as humanly possible with the information and considerations I had at the time. But after you cut a 14″ x 14″ hole in the roof and a 9″ x 21″ hole in the side (for the refrigerator vent), it seems kinda useless. That doesn’t even include any leaking door or window seals.
I’m lucky to have Teton Sports support my sleeping system and have a warm and comfy bed even in the winter, but waking up to 7-degrees Fahrenheit INSIDE my van in winter (without running my heater) is just……frigid.
So, does it even matter? If so, how much?
My gut tells me that yes, it does matter. That’s why if I could do it over again, even after writing this, I would still pay someone to professionally apply spray foam insulation. But without absolute proof, I still wonder if this whole topic is just a giant crapshoot.
What do you think? What type of insulation did you use in your van?
Let me know down below or send me an email: Info@VanLife.Academy
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**Disclaimers: There are a few affiliate links in here. Teton Sports also gave me my sleeping pads and bags, but asked for nothing in return. Also, I was paid for the original article I submitted to Teton as well.