I have a ply lined Hi Roof Tranny, I've used silver bubble wrap loft insulation (2 layers so far, might do another layer) on the metal roof, camping mats (2 layers) & carpet on the floor, raw sheeps fleece (from local farmers, washed a couple of times first!) behind the ply in the doors and planning to do same behind ply on sides, scraps of foam rubber stuffed into the roof ribs through little holes, and have stocked up on expanding foam to finish off all the nooks and crannies. Silver aluminium tape is good for taping the silver bubble wrap stuff together (spray glue to stick it to the metal), and also for any odd bits of exposed metal ie door bottoms and tops and sides.
The more insulation I keep adding, the better it's retaining the heat, noticeably. I've also got a double lined cab curtain with silver bubble wrap in between the layers - it makes the curtain a bit bulky when drawn back during the day but well worth it), I've also got curtains for sliding door and back door, and draught excluders for doors - all these make a massive difference. With my cooker on and all curtains closed, the temp can rise nearly 10 degs in 20 mins or so, and I don't get much condensation now, just a faint misting on very cold nights or in prolonged wet weather. Roof ventilation is always open even in the coldest weather. I was in the van recently and woke up and it was 6 C inside, and it wasn't till I opened the door I realised it was frosty outside so it must have been below zero during the night. So it was holding a fair amount of heat all night even without insulation behind the side ply yet. I've found that the condensation tends to be where the air can't circulate freely, ie towards the back of the van and on roof above shelving so will put extra layers of bubble wrap there.
I've also used silver bubble wrap and some Christmas window decoration suckers to make made to measure internal cab window screens for when not wilding and this really helps too. I'm also going to insulate the cab doors and cab floor too eventually.
And I've made a vertical draught excluder for the back door, out of camping mat, using drawing pins into the ply, as there was a walloping draught coming from the join in the back doors and up from the bottom of the doors.
The cheapest place for silver bubble wrap I've found is Wickes, about £11 per roll, B&Q was about £15 a roll, couldn't find it any cheaper online. I think I'm just starting my 3rd roll now, and have used about 8 camping mats and 3 rolls of aluminium tape, 3 cans spray glue. I use every scrap of camping mat and silver bubble wrap, even tiny bits can be stuffed into a gap somewhere and will help!
It's been a labour of love though, I've spent hours doing it, cutting bubble wrap to fit etc, and covering every inch of bare metal. Definitely easier to do it when the van is empty, not like I've done - doing it here and there whilst using the van and having to work around all my stuff. That's why I haven't done behind the side plys yet, as I'll have to empty the van to do that, so it really needs to be good weather to do it. And then in good weather, there's just too many other things to do instead.... :lol-053:
