First steps toward insulation

One big problem is that the whole box is metal. There are steel rods, and the panel surfaces are aluminium. When this van stands in the sun, the box metal heats up. I measured temperatures of 50 deg C. And naturally, this acts like a baking oven, heating up the whole interior of the camper. Unbearable to remain inside then. 

Even with the A/C on there is no relief: the A/C is not powerful enough to compensate for the heat; it keeps switching off because it appears to reach its limits.

So I need to insulate the whole box thoroughly. And I started with those metal beams which keep the roof in place. Got a few Styrofoam pipe insulators and placed them onto those beams. 

This insulation of the bars did not bring much relief: the Styrofoam temperature was still 35.5 deg C. All metal parts must be shielded from the inside of the box.