Insulating Our Camper Van
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The fan and windows were already installed in our camper van when we got it, so we were able to jump straight to cleaning out the van, installing sound deadening, and installing insulation. One of the most important parts of a camper van conversion is insulation, especially when you plan to go on winter van adventures, so we knew we had to take our time and do it right! Insulation helps keep in warmth in the winter and can also help keep the van cooler in the summer.
The previous owners of the van had installed a little bit of insulation already and some wiring. We pulled all that out so we had a blank slate to work with. Then we removed the factory floor that came with the van. This ended up taking longer than expected because some of the bolts holding the floor down were stripped. Kevin ended up using some creative methods to remove them :-).
Using and angle grinder to remove a stubborn bolt
Once we got the floor up, we cleaned all the metal throughout the van. We treated any rust with Rust-Oleum Rust Dissolver Gel and then used spray paint to touch up scratches. Treating rust earlier on is essential to reducing long term issues. Once everything was dry, we could start the process of installing sound deadener.
Installing KILMAT Sound Deadening Mat
Rolling out the KILMAT
Materials and Tools Needed:
- KILMAT
- Sound Deadener Roller Tool
- Utility Knife
- Heat Gun (if temps are too low to roll out)
We used KILMAT sound deadener all throughout the floors, walls, and ceiling of the van. Cargo vans are loud enough, so anything to reduce noise is great. Also conversations are easier when you can hear each other while driving. It was pretty easy to install since it’s peel and stick. We cut it to the desired size, stuck it to the metal, and used a roller to make sure it was properly adhered. The KILMAT has raised dots on it and you know it’s adhered once they flatten out. The temperature dropped while we were applying the KILMAT so we had to use a heat gun to heat it up before we could roll it out since it was too cold.
Choosing Insulation
After installing the sound deadening, the infamous debate of which insulation to use began. We had seen people use Havelock Wool, spray foam insulation, XPS board, Thinsulate, and many other options. The type of insulation you choose depends on what type of climates you will be in and what you feel comfortable installing.
Time for a little science lesson. The three processes that transfer heat are radiation, conduction, and convection. Conduction deals with direct contact, for example you touch a hot surface. Radiation by definition is the transfer of heat through electromagnetic waves. Stand close to a fire place and the heat you are feeling is being transferred by radiation. So is the heat you feel from the sun when outside. Convection is the transfer of heat through air or a medium. Think of air being pushed into your house when you open a window. These are all things we need to think about when insulating a van. If you have a dark colored van like we do, it will absorb more radiant heat, so the color of your van definitely matters. Radiant heat does not just sit on the outside of the van, it moves to other parts of the van through conduction and causes the inside of the van to heat up. In the winter when heating the van, hot air rises. If you don’t have ceiling insulation it can escape through the roof of the van and you will lose at lot of your heat.
You will hear the term R-values a lot when researching insulation. The R-value measures the ability of the insulation to stop heat traveling through it. Insulation with a higher R-value is more effective at stopping heat. If you are in a climate that doesn’t get super hot or cold you don’t need to worry about high R-values. However, most people want to be able to take their vans in different climates and be comfortable. We wanted to find a combination of insulation that had decent R-values and was also cost effective.
Other things to consider are the road vibrations and bumps. We didn’t want to worry about something coming apart or falling off so we elected not to do spray foam insulation. We were also concerned about moisture in the van, so we didn’t want to get something that was susceptible to mold or mildew. In the end, we chose to use XPS board for the floors, Thinsulate for the walls, ceiling and door panels, and Ez-cool for posts and other exposed metal areas on the walls and ceiling. The XPS board has an R-value of 5 and the Thinsulate has an R-value of 3.3. Hopefully this helps make your decision on choosing insulation easier!
Insulating the Floor
XPS Foam Board insulation
Materials and Tools Needed:
- 1/4 inch Fanfold Board Insulation for ridges in the floor
- 1 inch XPS Foam Board
- Great Stuff Gaps & Cracks Spray Foam
- Loctite PL300 (for foam board)
- Caulk Gun
As mentioned above, we elected to use XPS board to insulate the floor. The floor in the Sprinter has grooves, so we used 1/4 inch fanfold board to fill in the grooves to level out the floor. We glued it to the floor using Great Stuff spray foam. This process was tedious and isn’t perfect for eliminating gaps, but it was definitely worth the time and effort. Using the factory floor as a template, we used a utilty knife to cut the 1 inch XPS foam board to the shape of the van floor. Then we glued it down using Loctite PL300 adhesive. You can also use GE Advanced Silicone. It's important to use an adhesive that won’t break down the XPS foam board. We put weights on top of the foam board to hold it in place while the adhesive dried. Then we went around and filled any gaps around the edges with Great Stuff spray foam. Just to make sure nothing would move, we also bolted the XPS board to the floor of the van using the bolts from the factory floor. Overall, we are happy with our choice of XPS board to insulate the floor and would do it the same way if we had to do it all over again. Along with having a decent R-value, the 1 inch thickness doesn’t take away a lot of interior height, and the XPS board can support a decent amount of weight which is important for the van floor.
Insulating the Walls, Ceiling, and Door Panels
Fully insulated van
Materials and Tools Needed:
We elected to use Thinsulate in the wall, ceiling, and door panels. Thinsulate has a decent R value at 3.3 which isn’t as high as other options, but other van builders have used it successfully. It's super easy to install and remove if necessary and also helps with sound deadening. We installed the Thinsulate in the panels in the walls, ceiling, and doors. We used scissors to cut it to size and then glued it to the walls, ceiling, and doors with 3M 90 adhesive spray. We also stuffed it in the headliner above the front seats.
After this, we glued the Ez-cool reflective insulation to all the posts, beams, and other exposed metal areas throughout the van. The reason for adding Ez-cool was because the Thinsulate didn’t cover all metal areas in the van. Installing it over exposed metal helps reduce heat loss. We used the same 3M 90 adhesive spray for this insulation. We cut openings into the Ez-cool to allow for air flow and prevent moisture build up.
Final Thoughts
Overall, we are very happy with how we insulated the van and would do it the same way if we had to do it again. Since we have a lot of large windows, we made winter window covers out of leftover Thinsulate and LowEz cool for extra help in keeping the heat in and the cold out. We’ve taken the van on a couple winter adventures and our heater had no problem keeping the van warm at below freezing temperatures!