This information has just been added to an Eriba Facebook page so I thought it might be useful to record it here.(no mention of sheet thickness I'm afraid.)

EN AW-1050A (Aluminium Alloy 99,5, Cold-strengthened and annealed).Information provided by Bernd Mager.

In my experience this material cannot be rapid age hardened and in terms of aluminium alloy, is quite soft. For example, normal architectural and commercial alloys are 6063 and 6082 which can be age hardened and are only approx. 98.5% pure.

https://www.smithmetal.com/pdf/aluminium/1xxx/1050a.pdf

http://www.smithshp.com/metals/commercia...nium-alloys.htm

For folk with older vans the finish is called Stucco. Stuco.jpg - Bild entfernt (keine Rechte)

Randa