Had an flat roof single storey extension built just under two years ago - there are some 18mm plywood fascias just below roof height, which we dutifully primed and painted.
Had a pre-winter inspection today and found the ply had been merrily disintegrating underneath the paintwork. In a couple of places my trusty screwdriver now goes the full distance through it with ease.
Looks like the whole panel will need ripping out and replacing. Given that it's so new, obviously I'm not a happy bunny.
Anyone have any experience of this kind of nonsense? Can 18mm ply ever be expected to stand up to this, or should we have treated it differently?