Thanks everyone for your advice. We've decided not to paint them as we can't get access to the roof space and the seams are in different places compar ...

Hi again, After looking at it more closely, we've noticed that in some areas the plywood panels do not line up with each other well as there is some b ...

Thanks very much! We will give this a go and hopefully we can do it properly and it doesn't leave lines after painting. Much appreciated.