Great question!
Yes, the recycled plastic insulation (like our Thermo Fleece) is suitable for insulating your van roof — it's lightweight, non-irritant, and easy to fit. A lot of people do insulate the roof to help with temperature control and reduce condensation.
Some forums mention not insulating the roof because of moisture build-up, but as long as you pair the fleece with a vapour barrier layer (like GlassMAT XR or foil tape over joins), you’re good to go. Proper ventilation also helps a lot.
Cheers,
John
