Water water everywhere
I noticed yesterday that the brickwork wall outside the house bathroom was looking a bit damp so asked Wochiech to investigate today.
I've looked through old images to see if I could work out if it was a new problem or old and it appears it's very old and we've just missed it
Wochiech found the bathroom sink waste pipe was a mix of a variety of pipes joined together, not all the same size. Much of the waste water was going into the wall!