In a first floor bedroom, on the chimney breast on an external wall. Literally overnight, about 6 damp patches appeared. No extreme weather, the gutters look ok. We have open fireplaces and had the chimney swept a few months ago. The external isn't particularly exposed and the brickwork looks ok, but we'll get someone in to check it out.
We're a bit baffled. Any ideas? First step get the brickwork checked, second step get the chimney checked??