So i set about insualting it.
Step 1(removing panel)
This is how it looks nice pink:lol:
Firstly unscrew all the door panel holding screws.
Remove the little cap on the handle then the handle
Remove the door card

Step 2(adding sound deadening)
Clean the inside of the panel with a solvent(i used autoglym tar remover)
Gently warm the panel with a hairdryer and gently apply the sound deadening(rember only a little bit in the middle of a panel will ad deadedning properties but i added a bit more)

Step 3 adding celotex
This stage will add a good degree of insulation
Measure small pieces about half the size of the void to fill(you wont do it with one piece)
Cut carefuly with sharp craft knife
Gently jam it in tight
Secure with tape
Avoid mechanism

Step 4(adding bubblewrap)
Measure then cut bubble wrap to size
stick with tape
Avoid mechanism

Step 5 (vapour barrier)
I will next add a layer of clear polythene over the lot to act as a vapour barrier liek on the front doors
Foot notes
1)Both the bubble wrap and celotex are flame retardant(ce rated)
2)Both the bubble wrap and celotex are very light weight
3)The tape i used is waterproof remember condensation gets behind there normal gaffa tape wont last
4)dont press to hard when applying anything its your vans outer panel remember
5)Both products do not retain water very important
6)Do't go too mad with filling every little space some bretahing space is good.
7)On my van if condensation did build up behind the panels theres factory holes for it to drain from.
Prices
Thermawrap £13 a roll(long enough to do a van)
Celotex(25mm thick) £17 a 8"x4" sheet(enough to do panels on rear of a van)
Water proof tape £4 a roll (id go for 6 rolls to do all rear panels)
All from wickes