Here is our guide on DIY camper van conversion insulation with 3M Thinsulate. The Thinsulate insulation, the EZ-Cool insulation, the insulated window covers, the Webasto AirTop 2000 STC air heater and the Maxxair Fan are the key elements to make our campervan conversion comfortable during cold winter days and during hot summer days. We’re happy to report that after living for more than a year full time in the van, the Thinsulate insulation is keeping us nice and warm at temperature down to -15F (-25C) and is keeping the moisture away even when drying our skiing gear! Perfect!
How does our insulation performs? Please read “On Second Thought” at the bottom of this page! We have a thorough discussion about that 🙂
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TIME SPENT ON THE JOB
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- 3M Thinsulate (SM600L) Insulation, 70 linear feet (Buy from Amazon)
- Note that we have the High-Roof, Extended-Length; you might need less than 70 linear feet if insulating a smaller van!
- 3M 90 spray adhesive, QTY = 4 (Buy from Amazon, it should be around $10-$15 per can)
- A good pair of scissor
Installing the Insulation in our Van
- The floor thermal insulation is covered in our Floor Installation post. So let’s focus on the van walls and ceiling here.
- Our thermal insulation is comprised of Thinsulate and Low-E EZ-Cool. The Thinsulate installation is covered in this post while the Low-E EZ-Cool installation will be covered in Part II (wait for it…).
As much as the decision to go with Thinsulate was difficult, the installation was an easy task:
- cut thinsulate to size (using kitchen scissors)
- apply 3M 90 spray adhesive to the van wall & on the white face of the thinsulate
- wait 30-60 seconds for the adhesive to become tacky
- press the thinsulate against the wall
- That’s all!
OVERHEAD STORAGE ABOVE DRIVER & PASSENGER SEATS
There is about 1.5″ gap between the van ceiling & overhead storage, that’s perfect to insert some insulation in there. We did not use adhesive since the gap is about the same as the Thinsulate thickness.
No need to completely remove the overhead storage; we slightly lowered it a few inches to fit the Thinsulate as follows:
First, we removed both foam pieces on each side of the overhead storage
We used vise-grip and raw power to remove the pins (they were not damaged in the process and we were able to reuse them)
Foam pieces removed
Then, we removed the four screws (total) under the left-side and right-side handles
Next, we unsnapped the three pins in the center of the overhead storage
To unsnap them, the overhead storage must be pushed forward. This is quite tricky, keep calm! Some people have damaged them in the process, but they can be glued back in place later…
It is now possible to lower the overhead storage a few inches and install the Thinsulate
We used tree pieces of insulation to fill the gap: one on the left-hand side, one on the right-hand side and one in the center.
Reinstall the fasteners and VOILÀ!
The challenge with the ceiling is to work against gravity. However it proved to be fairly easy for 2 people. We won’t go in details here, because there is not much to say…
We left the Thinsulate as shown in the picture above for several months and we did not loose a piece. The 3M 90 spray adhesive is doing a great job!
Large cutout were filled with insulation.
We also filled the van cavities where possible.
The plastic panel must first be removed.
The panel is fastened with several push pins. They are fairly easy to remove with a flat screwdriver, or you can do it with a push pin pliers.
Since the sliding door is exposed to exterior elements, there is a plastic sheet to protect the door mechanism. The plastic sheet can be removed simply by pulling it; the goo should remained glued to it for later re-assembly.
Thinsulate was then placed in the cutouts.
Then just reinstall the plastic sheet and the plastic panel.
EDIT: “We’re done with the Thinsulate”. Euh, no we’re not! We also added some under the passenger seat base (after installing the Webasto Air Heater) and to the driver and passenger doors (while upgrading the factory speakers).
We could go on forever about R values, thermal bridge, etc, but here are the real questions:
Q: How does our insulation solution (Thinsulate, EZ-Cool and Insulated Window Covers) perform in real life?
A: It’s GREAT! It does what it’s suppose to: keep us warm in winter, keep us cool in summer.
Q: If we had to start over, would we go the same route again?
Now, here is a more thorough discussion:
1- On a very hot and sunny day, the Magnetic Grey sheet metal of our Ford Transit is burning hot. The Thinsulate is warm-hot, but the wood paneling is warm-cool. It shows that Thinsulate alone is fine, but the finished van (thinsulate+ez-cool+wood paneling) is even better! (It might be wise to choose a van with light color if you are living in a hot and sunny region)
2- If the van is left in the sun without the insulated window covers, the temperature will increase beyond our comfort level (ventilation or not); if the window covers are installed, we can keep the van within our comfort level (with the help of the Maxxair fan).
On any cold day (the colder we’ve experience is -15F, that’s -27C) it’s possible to keep the van to our comfort level (66-68F / 18-20C) when running the Webasto heater.
But what if we turn off the Webasto heater? Does our insulation solution will maintain the ambient temperature for a while? The answer is YES, if the insulated window covers are installed (if the window covers are removed, the temperature drop much faster AND it gets uncomfortable near the windows). In fact, we took the habit of turning the heater off when going to bed to turn it back on when we wake up (or use the MultiControl timer to automatically turn it on 30 minutes before we wake up). The temperature drop during the night, of course, will vary a lot with the outside temperature:
-Outside temperature of 50F (10C) in the evening dropping down to 28F (-2C) in the morning: the temperature inside the van will go from about 68F (20C) in the evening and will drop down to about 50-53F (10-12C) in the morning. (remember, we turned off the Webasto heater when going to bed)
-Below what outside temperature do we need to leave the Webasto heater running all night? We still don’t know, wait for it! We spent a week at -10F/-15F (-20 to -27C) last year in the Chic-Chocs (faroutride.com/chic-chocs-winter-wonderland-december-2016), but we didn’t have insulated window covers at that time and our insulation was about halfway done (no ez-cool), so we cannot draw real conclusions from that trip.
We can conclude that insulating a van is not only about Thinsulate, or spray foam; it’s about the combination of different items. In our case: Thinsulate, Ez-Cool, Wood Paneling and Insulated Window Covers.
About thermal bridge:
This photo was taken during the conversion without ez-cool installed; it means all the frames inside the van had no insulation on them:
It was a cold and damp morning (37F) and we were heating the van with the Webasto heater (55F). Note that there was condensation everywhere outside (on the van, on the ground, etc).
We observe that condensation remains where Thinsulate is installed, but this condensation is “evaporated” at the frame locations where there is no Thinsulate. This is because the frames are forming a thermal bridge for the heat to be conducted from the inside to the outside of the vehicle, thus providing enough heat for the water to evaporate. In other words, there is heat loss where there is no condensation.
We also observed inside the van that the Thinsulate is warm to the touch, while the adjacent “bare” metal frames are cold to to the touch. The Thinsulate is doing it’s job, the bare metal form a thermal bridge.
To minimize the thermal bridges, we will apply Low-E EZ-Cool to the “bare” frames (the wood finish will helps as well). The EZ-Cool is a closed-cell foam sandwiched between two aluminum sheets.
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Hello! We’re Isabelle and Antoine 🙂 In 2017 we sold our house (and everything in it), quit our engineering careers and moved into our self built campervan. We’ve been on the road since then and every day is an opportunity for a new adventure; we’re chasing our dreams and hopefully it inspires others to do the same!
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