Heavy insulation foil for a van conversion, yes or no? Some swear by it, others think it’s just extra weight that can be used for other things during the conversion.
We decided in favor of it. Now in retrospect, we are already a few weeks on the road with the bus, we are very happy about it. We had enough leeway with the weight of all our luggage and when driving we are happy that our bus is pleasantly quiet to drive without too many annoying noises.

What is actually a heavy insulation foil?

Very roughly described, a van is a tin box. Just as a tin box sounds tinny when vibrated or tapped, so does our van. In addition, there are the uncontrollable vibrations when driving. In order to keep these unpleasant noises to a minimum, the individual sheet metal surfaces must be weighted down. This is achieved by applying heavy insulating foil. The exact name of the material is Alubutyl. It consists mainly of a thick aluminum foil and a heavy, rubber-like mass.

Processing

Alubutyl comes in rolls of different widths – in our case these were about 40cm by 2m. Using tin snips, we roughly cut the pieces to cover about 1/3 of the area per larger section of sheet metal. It is not necessary to cover the whole car body with this heavy insulation foil. It is enough to weigh down the sheet metal so much that the vibrations cannot spread easily. Secondary is also the thermal insulation. Where there is more wall thickness, heat is less easily conducted from the inside to the outside and vice versa. The foil pieces are glued on by means of the self-adhesive side. Simply peel off the protective adhesive film and stick the Alubutyl to the dry, dust-free surface of the sheet metal without trapping any air.

But be careful; the aluminum foil is sharp-edged and can quickly lead to cuts, so better not forget to wear work gloves!