Thank you for replying and for the links... I just wondered how PDL differs from Brownfield land as when I call it brownfield, the planning dept correct it to Previously Developed Land...
I have a plot with a redundant building on it which is on the green belt and wondering about the development potential... Greenbelt obviously goes against residential development (unless you have the means to pay a substantial amount towards 'mitigation of the environmental damage caused by development'... whatever that is, but sounds like free money for the council) and this building has been stripped of its permitted development rights by an article 4 direction... whether this can be revoked or not remains to be seen.