The "GPDO Part 1 (All Classes) - LDC Appeal Decisions" document has been updated to include 2 additional appeal decisions relating to householder permitted development legislation, for which the conclusions are as follows:

December 2019 - Code a01100 (appeal allowed):

• This appeal decision provides an example of where it was concluded that a proposed roof extension (under Class B) should not be treated as two separate proposed roof extensions (under Class B) for the purposes of the phrase “the enlargement” within B.2(b). [Note: In other words, the combined structure should be assessed against those limitations and conditions of Class B that apply to “the enlargement”]. (*)
  [Note: Relates to an “L”-shaped roof extension (or similar), and the Inspector refers to "a single structure"].
  [Quote: “The Council has considered the proposed development as joining a dormer to a dormer. This is misconceived since, in my view, it is only appropriate to consider the proposed L-shaped dormer as one discrete operation not separate out its constituent parts. The proposed L-shaped dormer would be a single structure, and so, as a matter of fact and degree, it would be an enlargement which joins the main roof to the roof of the outrigger and conditions B.2(b)(i)(aa) and B.2(b)(ii) do not apply.”].
• This appeal decision provides an example of where it was concluded that a particular roof extension does constitute “an enlargement which joins the original roof to the roof of a rear or side extension” for the purposes of B.2(b). (*)
  [Note: The proposed roof extension would join the main rear roof onto the pitched roof of the original two-storey rear projection].
• For the purposes of the post-06/04/2014 version(s) of Part 1 of the GPDO, where a property has an original rear projection with a side-facing pitched roof, part of which is lower than the main rear roof, then an “L”-shaped roof extension (or similar) that extends from the main rear roof onto the side roof of the original rear projection is permitted development. [Note: The roof extension, for part of its (rearmost) width, extends across the original rear eaves]. (*)
  [Conclusion: The works comply with Class B. In particular, the works comply with B.2(b) on the basis that the roof extension does constitute “an enlargement which joins the original roof to the roof of a rear or side extension”].
• Where a property has a secondary roof that’s slightly lower than the main roof, then an extension on top of this secondary roof should be assessed against Class B (i.e. rather than Class A). (*)
  [Note: The secondary roof is the roof of an original two-storey rear projection on a two-storey house].
• The phrase “the highest part of the ... roof” relates to the property as a whole (i.e. not only to the part of the property that’s being altered or enlarged). (*)
• For example, where a property has a secondary roof that’s lower than the main roof, then an extension on top of this secondary roof can be higher than the highest part of this secondary roof (i.e. so long as the extension is not higher than the highest part of the main roof).
  [Note: The extension is higher than the ridge-line of the original two-storey rear projection].

December 2019 - Code a01099 (appeal dismissed):

• [Note: To view these conclusions, please log onto the website as a member].

Notes:

• To view the conclusions, summaries, and decision notices for any of the above appeals, please view the "GPDO Part 1 (All Classes) - LDC Appeal Decisions" document. As a member of the Planning Jungle website, you can view the decision notices for all of the appeals on the website for no extra cost.
• Any of the above conclusions marked with a "(*)" contradict other appeal decisions. The "Reference Section" within the above document indicates how many appeals have supported and contradicted each particular conclusion.