Hi,

What is the easiest way to fill the channels in the roof of my campervan (before adding a solar panel).  The attached picture shows the size of the channels.  Could I just make a lightweight filler with glass bubbles and fill the entire void?

My assumption is that the roof is GRP sprayed with car spray.  There is a fair amount of flex/twist as the roof goes up and down, although I'd say that is fairly minimal along the ridges themselves.

Many thanks