Best insulation for a Sprinter conversion in the UK climate?
I'm starting my Sprinter LWB build and can't decide on insulation. I've seen people use everything from Celotex to spray foam to sheep's wool. Given the UK's damp climate with condensation being a real issue, what's the best approach? I'm leaning towards closed-cell spray foam for the walls and Thermawrap for the ceiling. Budget is around £500 for the whole van. Has anyone had issues with condensation using rigid board insulation?
5 Answers
I went with 25mm Celotex on the walls with Thermawrap over the top, and it's been brilliant. The key to avoiding condensation is the vapour barrier — make sure you seal every join with foil tape. I've been living in my Sprinter full-time for 18 months now and haven't had any condensation issues. The Thermawrap acts as both a radiant barrier and vapour barrier. Total cost was about £350 for the whole van. One tip: don't forget to insulate the floor — I used 10mm closed-cell foam under the ply and it makes a huge difference.
I used sheep's wool insulation (Black Mountain brand) and absolutely love it. It naturally manages moisture which is perfect for the UK climate. It's a bit more expensive than Celotex but the breathability is worth it. I paired it with a Tyvek membrane rather than a full vapour barrier, which allows the van to breathe while still keeping moisture out of the insulation. No condensation problems after 2 years of weekend use.
Great question! Here is my test answer with helpful information.
Great question! Here is my test answer with helpful information.
Great question! Here is my test answer with helpful information.
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