Thanks very much for the advice and I'll certainly take on board what you've said. I never thought of it from that angle Jason.... In fact, I've got connections in the building trade.... Mmmmmm!
Colin, most builders wouldn't know what to do about these situations if it was growing out their ears. And that goes for a lot of Chartered surveyors as well.
Like Jason we do this work in a seperate business. Its a big problem especially in double glazed properties where the moisture created by cooking, washing, drying clothes, even breathing, can't escape and ends up condensing in the fabric of the building. It is very serious. Every square centimetre of visible mould (the visible part is only the fruiting body and a small part of the actual fungus) can give off up to 200, 000 fungal spores. These can cause long term lung and even brain damage.
By the way that one looks more like a penetrating damp issue. Anyone with similar problems contact a surveyor from here:
http://www.isse.org.uk/ they should be able to help or advise you.