Paneling and insulation

The van was already lined with 6mm ply and it was done with 10'0 sheets too,so, even though they were a little grubby, as they were going to be covered with carpet we decided to reuse them but they had to come off first in order to insulate.
Now I read and read up on the best insulation and the best way to insulate and found pro's and cons to most, but what did seem to stand out was the two products that kept on getting mentioned were kingspan and what I can only describe as foil backed close cell neoprene type foam. I decided to go for a combination of both in the end.The Kingspan is very popular in housebuilding, It is basically like flat sheets of the expanding foam with a silver foil on both sides. I cut it mainly like plasterboard,score one side and then stick yer knee in the other side to split it down the joint. This was used to insulate the floor which already had a factory fitted 9mm plastic coated ply down, I used 25mm x 45mm lengths of timber spaced about 300mm apart then filled the gaps with kingspan which was 25mm thick. I then topped it all with another 9mm exterior grade ply, just in case it ever got damp, you hear all sorts of horror stories about de-laminating.
One thing I did discover and that was that you really do need to be thinking ten jobs in front of what you are doing today and plan way in advance. This is why you need a pretty good idea of where stuff is going as it's a real good idea to run a couple of ducts (just spaces really) between the floor sandwich for cables, water and gas pipes.
We also did the ceiling with the same size kingspan, between the structural spars though again, it's a good idea to put 20mm x 45mm timber from one side to the other first on all of these to fasten the ceiling ply to. As the roof is bowed, I put one piece across the centre first to within about 300mm of the sides then put a small piece in then on each side so the ceiling was straight and then just has a little slope on the sides. These were all fixed with sikaflex adhesive and a couple of strong self tappers.

The walls were done wherever we could reach with the stuff I don't know the name of. I got it off the internet actually, never found it anywhere else. It comes by the metre as long as you want, and I actually rang the guy in Cleckheaton who was very helpful as he gave me a pretty good idea as to how much a Sprinter would take, so as neither of these products are cheap, I didn't want to finish up with a load left. This stuff anyroad, It has a bako type silver foil on one side, then about 6mm of what looks like neoprene, and if you've ever worn on, you know how warm a wet suit is, then, it has a greaseproof type paper which pulls off to expose what can only be described as the stickiest bloody glue you've ever come across in your life! It is a high temperature adhesive (so it won't come off while you're sunning yourself somewhere hot). It's very difficult to get in a lot of the places so just cut it into smaller bits as it doesn't matter what it looks like as no one is gonna see it again. You may think, oh, it doesn't matter if I don't do this bit or that bit but it does. What amazed me was, I did just about everywhere except the bottom of the ribs on the ceiling as I wanted the ply to sit as high as I could. I got to fitting the ceiling ply and that was more or less touching the ribs. Next morning we'd had a heavy frost, I was gobsmacked when I looked inside, each rib showed through the ply with a damp stripe, condensation I presume. Luckily, I had only put two pieces up so I took them down and stuck the insulation on them. I think I can say that the insulation part is the slowest most tedious part of the job,and I've watched paint dry, followed by the paneling, but it really does pay dividends in the long run to get it right. It's also a good idea to take pictures and map out where all the batons and good fixing areas are.