Part II of our Ram Promaster insulation highlights the floor and how we tackled the project. Check out how we insulated the walls and ceiling of our Promaster here.
Insulating the floor of our Ram Promaster was a pretty straightforward procedure. The only unknown piece of the puzzle was removing the factory floor, something that I wasn’t very keen to do. The floor is quite nice, and we wanted to use it as our finished flooring. Keeping damage to a minimum was a top priority.
Removing the factory floor actually wasn’t too bad. We took our time prying up little sections, moving from side to side and supporting the floor as we went worked well. Having a long 2×4 was the most valuable tool to have for the removal.
The hardest part of removing the floor was actually getting it out of the van by myself, I’d highly suggest having someone help you for this step.
The level of damage to the factory floor was minimal, I’m calling this a success! For reference, it took me about 45 minutes to get the floor out of the van.
Moving on to the insulation, we decided to continue using 1″ polyiso like we did on the walls and ceiling. We went back and forth between 1/2″ and 1″ multiple times, in the end the 1″ won out. We calculated that we’d still have about 6’2″ of headroom once everything was finished inside the van, which is adequate for us.
The best part about removing the factory floor was that we now had a template to use! Tracing the polyiso was a breeze and made for a nice fit inside the van.
After test fitting the insulation, it was time to secure the pieces down. We went with Great Stuff Pro for the job. We like that it’s a very good adhesive, it helps fill in some of the gaps and low points in the floor, and that it doesn’t set/cure instantly. After everything was foamed up, we put as many heavy things as we could find on the polyiso to hold it in place.
Following the foam it was time for the 1/4″ plywood. I’m not sure if this layer was completely necessary, but I’m glad I did it. I wanted the piece of mind of another solid layer to screw into and add support. We basically followed the same steps as the polyiso above; trace, test fit, adhere with foam, and add weight.
If you plan to use the factory tie downs, don’t forget to cut out holes before you glue everything down. I don’t know if I’ll use them in the future, but I wanted the option. I also like the idea of them helping to the hold the floor in place. You’ll need to get longer bolts to use the tie downs. I went with M8-1.25 x 60mm bolts.
The final step is to put the factory floor back in, which was easier said than done. This time my lovely assistant was around to help me wrangle the beast. I wasn’t able to snag any pictures of the process, probably because we were getting owned by the floor, but we followed the same steps as before; spray foam, weight, and then wait.
The final product! It’s kinda sad that to the untrained eye nothing has changed, but it felt like a very productive 7 hours!
- Take your time prying up the factory floor, a couple minutes isn’t worth potential damage
- Use the factory floor as a template!
- Run the polyiso and plywood in different directions, you don’t want the seams to line up
- Make sure everything fits before you glue it down
- Don’t forget longer bolts for the tie downs if you plan to use them
- Find someone to help you with the floor removal