Thought long and hard whether this should go in Roofing and Guttering, but it seemed the most appropriate place.
My problem is hopefully self-evident from the images below: horribly stained lead flashing. It looks even worse since these photos were taken because the tatty timber windows have been replaced with new uPVC ones. I've no idea what causes this discoloration. I've tried wire brushing a small section but couldn't shift it.
Any ideas please for possible courses of action? Thanks in advance.
My problem is hopefully self-evident from the images below: horribly stained lead flashing. It looks even worse since these photos were taken because the tatty timber windows have been replaced with new uPVC ones. I've no idea what causes this discoloration. I've tried wire brushing a small section but couldn't shift it.
Any ideas please for possible courses of action? Thanks in advance.