Around two years ago we installed Galvalume sheets for roofing. As you can see in the images below, the trusses were given only epoxy coating. We were told by the roofing contractor that paint over that coating would not be necessary.
However, now we are seeing the epoxy coating 'chalking out' i.e., it's just powdering and falling off exposing the metal surface. While we are keen on repainting the trusses, the concern is there is hardly any space between the sheet and upper surface of the trusses. Is there any solution to paint all the sides of the sections without detaching the sheets? Also, would it be essential to remove this existing layer of epoxy for the paint to stick?