What is this green stain?

It looks organic. A nice strong house wash mix should do it. X jet or 12v.

If you can’t see it that well, it has a greenish hint, like you would see with copper patina… or whatever that’s called.

They just had their gutters replaced. I don’t see any copper flashing or anything.

It is not organic… it got blasted today with the roof pump.

this is a before photo, so I know why you would say that. Just imagine all of the organic stuff around it gone and that greenish hint remaining. I will send an after as soon as it dries…

Okay. I misunderstood. No I cant really see the green tint but ill take your word for it. My best guess would be that it might clean up with an acid then. I’ve used clr on a pinch but I carry f9 barc and efflo now. Hope you get it figured out.

@Racer @squidskc

So the green is rust?

I dont know. Probably not. But it might be something that leached from the previous gutters. Was there a downspout there? Paint maybe? I still can’t see the green really. Is the brick degraded there? Or maybe that areas been covered by a downspout and the rest of the building faded slightly. Just speculation. I’d do some test spots at the bottom of the building.

If there was no copper it can be iron rust called fougerite if it’s green as I understand it. Like @Clean1 said a spray bottle with some F9 or Rust Remover Plus or oxalic mix for test spots will answer your question.

Also, bleach will turn copper black so if it were copper those streaks would likely be black.

If you don’t have F9, RR+, or oxalic, you can test a small spot with Iron Out or behr deck cleaner. But I wouldn’t use it on the entire application. But a quarter sized test spot with tell you if you need to order some.

@Clean1 @squidskc
Ok, I will go test it Monday. I think I have some F9, still.

What about the red tip?

Just kidding please post results.