Don't have access anymore to flat. It's a bedroom with one window (one in picture) mid sized room.Second pic is too dark to see anything.
First pic, possibly. Might want to post more pics of the larger area of the wall / room plus, pics of the other side of the wall.
So opening window would help, howcyou check the seal? Damp meter in wall would help?By a window likely condensation or poorly sealed frame .
That's coming from bathroom. The shower isn't electric but heated from an immersion- crazy.I think you've answered your own question
Where is that pipe through the wall coming from? Looks like a hot water cylinder relief vent which means its probably got a fault.
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