The "GPDO Part 1 (All Classes) - LDC Appeal Decisions" document has been updated to include 5 additional appeal decisions relating to householder permitted development legislation, for which the conclusions are as follows:

March 2020 - Code a01150 (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 operational development"].
  [Quote: “The proposed development comprises an L-shaped dormer extension to the rear, creating accommodation in the attic space. Part of the box dormer would sit within the confines of the rear roof slope of the main building. The Council’s concern relates to the element of the proposed development that would extend over the rear outrigger roof, forming the L-shape. They consider that planning permission is required as this element fails to meet the requirements of permitted development in respect of [Part 1 Class A of the GPDO]. However, although the Council’s approach disaggregates the rear extension into two parts, the whole L-shaped structure should properly be considered as a single operational development. As the appeal development is an enlargement to the dwellinghouse, and falls to be considered as a whole rather than in its component parts, the most appropriate Class against which to assess it for permitted development purposes is Class B of Schedule 2, Part 1 of the GPDO.”].
• 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].
• 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].
• This appeal decision provides an example of where it was concluded that particular works do fall within the scope of Class B, on the basis that the works do not exceed what constitutes “the enlargement of a dwellinghouse consisting of an addition or alteration to its roof”. (*)
  [Note: The works include an “L”-shaped roof extension (or similar) that covers approx half of the roof of the rear projection].
  [Quote: “Furthermore, an issue has been raised about the original outrigger roof being subsumed and replaced by an extension, as opposed to a development that may be termed an extension to the roof. However, only around half of the outrigger roof would be removed, and for the reasons above, I am satisfied that the development falls within the scope of Class B.”].
• 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”].
• 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].

March 2020 - Code a01149 (appeal allowed):

• This appeal decision provides an example of the types of factors that should be taken into consideration when determining which elevation is “the principal elevation”.
• “The principal elevation” is not necessarily the elevation that contains the main entrance door.
• An elevation that’s opposite the “front” of the property must be “the rear wall”. (*)
  [Note: This appeal decision implies (rather than states) this conclusion].

March 2020 - Code a01148 (appeal dismissed):

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

March 2020 - Code a01147 (appeal dismissed):

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

March 2020 - Code a01146 (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.