Quote Originally Posted by Treemonkey View Post
By the looks of your pics the walls have the white flakey stuff efflorescense so its probably best to go for a breathable paint.
I gave the whole thing a quick once-over with a stiff brush and cleared the detritus from the vent, even that little bit of work makes a heck of a difference! There is some very clear efflorescence on part of one wall (just the top part though, the bottom part looks very clean. A lot of the white stuff appears to be some kind of flaking paint, it's almost like it was given a very light wash of something.

Thanks to the many fine suggestions from people both here and in PM! This shouldn't take me more than four or five years to complete :)