In this article I cover how I insulated the walls and ceiling in my van. After many hours of research and banging my head against a wall, I ended up going with Thinsulate for insulation.
Thinsulate is low weight, non-flammable, does not absorb moisture, doesn’t off-gas, is meant to be used in vehicles, etc. For those reasons, I felt safe installing it in my vehicle. Once you get templates cut out, installation is very easy. I ended up buying 40’ for my 136” WB Ram ProMaster.
The trick to the 3M adhesive is to spray it first on both the van and the thinsulate, let it set for a few minutes until it’s tacky, and then place the thinsulate. If you don’t let the adhesive sit, it will not cure/adhere the materials correctly.
4] Stuff thinsulate into all the nooks and crannies of the van. Remove the door panels and insulate in the van as well. I recommend picking up an auto trim removal tool kit for like $10 to remove all of the plastic pins.
In the next article, I’ll show you how I built a solar panel rack for my ProMaster.
In this article, I finish the van floor insulation and subfloor installation in my van. This took me a lot longer than I had anticipated, there are a lot of steps that require patience, creating templates, etc. I am stoked with how it turned out though, my floor feels super solid and secure.
1] Create a template with kraft paper for the entire subfloor. If you aren’t certain on your template, use a cheap piece of wood to test before cutting your nice plywood.
2] Cut out the subfloor with a jigsaw. Drop the pieces in and make sure they fit. Sand any areas that are tight. Leave 1/8″ – 1/4″ around the edges for flexing.
3] Prime the subfloor with mold & mildew resistant primer.
4] Use as many of the existing tie down threads to secure the subfloor with long M8x1.25 bolts.
5] Put a few screws into the subfloor, making sure to hit the 1×2’s that were installed underneath.
You shouldn’t need too many screws, just put a few in, see where things are still moving around, and continue adding screws until the floor feels secure. Keep in mind that you’ll most likely have cabinets and things on top to also secure the floor.
In this article I will cover how I insulated the floor in my Ram ProMaster van. I used 3/4″ RMax Polyiso rigid foam board for my insulation. However, I had a lot of trouble finding it in southern California, none of the big box stores carried it.
I ended up being able to custom order some through J&B Materials. They were super helpful, give them a call for any building supplies if you are in the area.
There are tons of hot takes in forums, articles, and on YouTube about the best insulation to use for the floor in a van. I’m not here to tell you what’s best, you can choose whatever you feel like works out best for your situation. There are a lot of good options to choose from – Polyiso, sprayfoam, minicell, etc. Or, skip the insulation altogether, drop in a quick subfloor, and use some heavy rugs.
I personally went with the Polyiso/grid solution because I didn’t want to drill holes into the floor of my van. The 1×2’s, along with the tie down threads, will allow for me to attach the subfloor securely, without creating new holes.
The flooring solution will all be centered around a grid of 1×2’s, so you’ll want to draw up a diagram of where you want your 1×2’s to sit in the van. The 1×2’s will be adhered to the floor, no screws will be going into the existing floor. We will be using the existing tie-down threads to secure the subfloor, as well as putting screws from the top layer down into the 1×2’s.
The insulation and sub floor are tied very closely together, so you’ll want to have your subfloor pieces cutout and ready to use for weighting down the adhesive overnight.
1] Create a grid with 1×2’s. This requires lot of measuring, patience, and cutting.
2] Cut the Polyiso to fit inside the grid. Make sure everything fits nice, but allow some room for the wood to flex.
3] Prime all of your wood with a mold/mildew resistant primer. Wait for the paint to dry.
4] Remove everything, remove the tie downs in the floor, clean the floor with Simple Green, and fill any holes with Sikaflex. If you will not be using the tie down threads at all, put a placeholder screw in the hole, or fill the hole with Sikaflex so water does not get into the van from underneath.
5] Put all of the 1×2’s and polyiso back into their spots.
6] Starting from the back, begin adhering the 1×2’s to the van floor by using the Loctite construction adhesive. Place weights on the 1×2’s. Continue going piece by piece until you get to your first seam. Use the 3M adhesive to put the polyiso in all of the voids, before the first seam.
The trick to the 3M adhesive is to spray it first on both the van and the polyiso, let it set for a few minutes until it’s tacky, and then place the polyiso. If you don’t let the adhesive sit, it will not cure/adhere the materials correctly.
Place your first piece of subfloor on top of the 1×2’s and polyiso, add weights on top.
7] Repeat step 6 for the rest of the pieces, go seam by seam until your subfloor is sitting in place with weights on top of everything. Let this sit overnight to ensure that everything has adhered to the van floor.
8] Sleep
9] Remove all of the weights and subfloor pieces. Verify the polyiso and 1×2’s are installed correctly. Give the 1×2’s a good yank, these should not move at all.
10] Spray any small voids with Great Stuff.
11] Tape off all of the seams with Reflectix Tape.
12] Take pictures and mark where all of your 1×2’s are so you can easily put screws into the wood during the subfloor installation.