Blister On Aluminium Finish!!

by Murray
(Glasgow)

As above I have a blister the size of a hand print on the side of the van but there is no sign of water ingress what so ever!! The panel if pressed with light pressure, does confirm there is a gap behind the metal i.e. the inner is not swollen. Is the panel applied to the inner using glue and if so is it known for the panel to blister due to heat i.e. sunlight? Thanks.

What has happened here is basically what is termed as delamination (adhesive bond failure). It can be fixed quite easily and you should really get this looked at as soon as possible before it gets worse.