I was looking at a five unit property yesterday and this strange discoloration is on the side of roof without algae. Each unit has the same thing. I am pretty sure it's from the copper caps because I see the same thing at the copper eyebrow vents. If we get the work (for spring) I already said I would do a test in the area of the cupola first to see what happens. Thoughts and ideas?
Ive always assumed this was the beginning of rust staining. I've seen similar on houses that i dont think had copper or copper flashing on them.
DirtyRoofcom said
Oct 28, 2018
I've been thinking about this... how could it be copper staining? Im consistently at upscale homes that have copper flashing everywhere (chimneys, cupola, gutters, roof wall intersections,etc) and dont see this in those spots.
I have seen black staining on some slate and tile roofs that I posted about a while back not sure what it was but F9 took care of it.
I was looking at a five unit property yesterday and this strange discoloration is on the side of roof without algae. Each unit has the same thing. I am pretty sure it's from the copper caps because I see the same thing at the copper eyebrow vents. If we get the work (for spring) I already said I would do a test in the area of the cupola first to see what happens. Thoughts and ideas?
It's not granule loss and the other sides were hard to see due to sun or the way they are built into hills. Here is a picture of the south side.
I have seen black staining on some slate and tile roofs that I posted about a while back not sure what it was but F9 took care of it.
www.nationalsoftwashalliance.com/t62297876/what-is-this/
as the coating breaks down , more light green stains, mainly at cut edges.
bare copper will oxidize over a large surface area faster and produce more staining.
that may be the difference from house to house.