To ask what you think this is on the outside of the window

[SassySugarCane]

If I didn't know any better I'd say it was moss. I live in a block of flats and we do get a lot of water trickling down. I am going to speak to the council in the morning and see what they say. I want to know what I should be telling them it is if it is indeed moss?

Gah if its not one thing its another.

Crafty bump

What am I supposed to be looking at? There's so much reflection in the photo I can't tell if you mean on the glass itself or the frame at the bottom. Sorry, but I just can't make out whatever it is.

Looks like algae to me

The green stuff. At the bottom. Probably would be best to take another picture in the morning. It couldn't be Algae could it?

If it is inside your double glazing then it means the seals have gone and the double glazing won't be working properly.
Your council should replace the seals.

It's algae. It means that that part of the window is frequently wet.

Not sure if it is inside the double glazing, I'll have a look in the morning when its lighter. Will ring the council either way and ask them.

Yeah I can always hear water dripping on to it. There are overflow pipes on the outside of the building so may be from that?

"Not sure if it is inside the double glazing"

Can you access the outside of the window yourself to try to clean it off, maybe with a long-handled brush?

Can't access it no. I am on the first floor and the gates at the bottom are padlocked so I can't get in at the bottom with a brush even if I had one that long. Else I'd be out this morning trying. It's disgusting to look at.

Anyway I have spoken to the council and they are sending someone out next week, to have a look. They are in the process of over-cladding all the blocks in the borough, white and grey edged. (Anyone watched People Like Us? That's where I live pretty much) so wouldn't look nice with green streaks down it. As other blocks I have walked past .. have all got at least one leaky overflow pipe and they have yuck stuff down the sides of them as well.

At least it will get sorted. Eventually.