The latest PD legislation, as per SC's link, came out in Oct '08. At the time, as is the case with most Gov't legislation, confusion reigned as to the correct interpretation of the wording therein. One particular example being the interpretation of Class A.1(e) ''extend beyond the rear wall of the original dwelling house..''. A lot of houses have more than one rear wall, so were you allowed to extend out from each rear wall or the furthest rear wall? Some Local Authority's interpreted it as the former, others the latter. It is only when trying to interpret legislation that confusion and anomolies will appear, no precedents have been set, and there are no similar case studies and/or planning appeal decisions to refer to. So, after nearly 2 years of feedback, the Gov't brought out a useful Technical Guidance in Aug '10 to help clarify the legislation, and hopefully overcome such confusion. On page 17 of the guide it clarifies what is acceptable in the rear wall scenario I cited above. Charlie, could you please clarify what part of the legislation you are referring to.