This is how I insulated the floor.
For those of you that haven’t seen the pictures of the inside of my van when I bought it, this is what it looked like
It was a mess. It had dried on cement, paint, holes, you name it it was there. After all of the rotted ply was out and I’d got everything that I could off the floor the first job was to fill all the small screw holes.
After the floor was water tight again I spent quite a few hours with a wire brush cleaning any loose paint away, then used Red-Oxide paint to seal all areas where the paint was damaged.
The next job was to fit 25mm battens where needed
I started from the bulk head, laying strips of 25 x 50mm batten at roughly 600mm intervals. This was because I’m using 25mm Kingspan type insulation everywhere I can in the van and it’s 1200mm wide so cut in half 600mm.
I continued this across the floor to the back of the van and added cross members where needed but never more than 600mm apart. I decided to add them, where possible, in the places I knew furniture would be so I have more to screw down into. These were glued into place using Stixall from Toolstation.
Once the glue was dry it was time to add the insulation, just a case of cutting the right sizes out and again sticking in place with a little Stixall. To finish it off I added spray foam insulation to any gaps.
In the middle of the above picture you can see an area where two battens are close together. My water tank is on one side of the van and my sink will be on the other. I needed a way of getting the water pipes from one side to the other so decided to run them through the floor. I was worried about any future leaks and not being able change the pipe so I decided to run two 25mm conduit pipes through the floor that I can then thread the water pipes through. These can easily be accessed from under the seat bases.
The next job was to trim the expanding foam flush with the rest of the floor. This is an easy job with a bread knife.
And then finally I added aluminium tape over all of the joints and battens. This was to give a vapour barrier.
That’s the floor insulated and this is also the method I’ve used for most of the walls and ceiling.
Next job is to fit the plywood on top.