Floor insulation

The rear part of the cargo area hs its own floor already installed. There is a underfloor, and on top is a blue vinyl. But that part ends where the rear seating area begins. If these seats are folded, then there is a sudden transition from that solid floor to the carpeted area which normally is under the rear seats. I want to have this all as one single area. So I started thinking how to do this. Best would be to remove the rear floor and make one common underfloor. But I was not able to remove that floor with easy means: after removing a few screws from those metal tracks (for attaching apparently loosely moving things, such as a wheel chair) I saw that the floor did not move at all, and those tracks / rails appeared to be glued tightly to the vehicle. So I decided that I would just cover it with another layer of underfloor and place my final floor on top of that.

The area under the rear seats is carpeted. I could remove this carpet, but I decided to leave it in as part of the insulation. I got a pack of Selitac floor underlay and placed it onto the carpet area, cutting out parts where hooks and installations (wrench, seat belt bolt) were protruding. Even though it said on the instructions that no adhesive was required, I put adhesive onto the carpet to ensure that this underlay would not move around. I also removed the door entrance floor panels, laid the underlay, and placed the panels back with those underlays pressed under them. The result is not very sturdy, as this foam underlay is a bit flexible. But it is a first basis for whatever comes on top.