I'm currently converting my van to a camper and looking for some recommendations for a vapour control layer/thermal insulator similar to Reflectix but hopefully not as expensive. Any suggestions?
I used B&Q recycled plastic bottle insulation (looks like sheep wool but by nature doesn't hold moisture) then topped thay interior side with foil backed bubble wrap, and taped joints with foil tape
I was going to use Celotex for the floor and roof and something like the B&Q insulation mentioned by Squashroinson. However after the terrible fire at Grenfell last year I'm no longer sure about the Celotex.
What exactly are you hoping to insulate your van against? Road noise or heat loss? I have a VW T5 which I've converted to a campervan, and I too insulated mine with the recycled plastic insulation, but I was mainly insulating against road noise. It worked OK, but at 70mph down the motorway, it still sounds like a van ... it will never sound like a luxury car. I would be very wary about using too much insulation or any insulation that might retain moisture. No matter what you do, your windows WILL steam up if you sleep in your van in cold weather with the windows fully closed. If you leave the windows even slightly open, you'll have far less condensation in the morning, but you'll also be nullifying the insulation you've just installed in all the cavities. If the weather gets really cold, like below 5 or even 10 degrees, there'll be so much condensation that it will run down off the windows and into the very spaces you've just insulated. Wet insulation is not just ineffective ... it's also a significant cause of rust. However well you insulate your walls, what do you plan to do about insulating your windows, which is where most heat loss will occur?
What would you suggest rogerk101? I’ll shortly be looking to insulate a van (against heat loss) and the damp issue is worrying. But I think to not insulate at all is not an option. And yes, how do you insulate windows? Surely if you have them sealed in correctly, any run off wouldn’t go between insulation/wall layers? My understanding of sound proofing is that you just need a small square of a specific material (can’t rmmbr name off top of my head) that dampens the sound reverb. Any advice much welcomed!
Some people insulate their windows with shiny bubble plastic and sucker pads, but I haven't tried that. I think it's a waste of time and effort trying too hard to insulate thermally. You can't prevent the biggest hassle which is condensation. I've never seen a campervan that hasn't had windows dripping with condensation when the weather is cold.
You could use a 12v heater/aircon unit if it was for a campervan. https://www.t7design.co.uk/products...ing-units/aircon-heater-combination-unit.html
Whatever insulation you use, fit a vapour barrier on the inside, the warm side just under the final finish.