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

November 2021 - Code a01363 (appeal allowed):

• The height of a structure should be measured from the highest part of the adjacent ground level (i.e. rather than from each part of the adjacent ground level). (*)
  [Note: The structure is an outbuilding].
• This appeal decision provides an example of where it was concluded that particular operations (e.g. engineering operations) do not constitute a separate activity of substance (e.g. with reference to the “Eatherley” High Court judgment dated 02/12/2016).
  [Quote: “Both of the main parties as well as neighbours have referred me to the case of Eatherley v London Borough of Camden & Ireland [2016] EWHC 1861 Admin. This case involved a proposed basement enlargement of a dwelling house, where the Court held that the excavations and underpinning involved amounted to a separate activity of substance from the construction of the basement which would follow. The judgement upheld the decision of West Bowers Farm Products v. Essex County Council (1985) 50 P & CR 368, where the Court held that the excavation of sand and gravel to create a reservoir to serve a farm constituted a separate operation for which there was no deemed planning permission under the permitted development regime. In Eatherley, the Court held that the appropriate question to be asked was whether the engineering operations required were a separate activity of substance, and that the assessment was a matter of planning judgement. In my view the construction of a raised base, slab or plinth on sloping ground is a normal part of the construction of a building, and the fact that there would be walls surrounding that base of up to about 0.8m or so in height does not result in it being a separate activity of substance. My views are reinforced by the finding of Cranston J. in Eatherley who commented that “engineering operations for the basement are at some point different in character to those involved in the preparation of foundations for a house”. Here, the construction of the base, plinth or slab is part of the preparations of foundations for the building proposed, and I consider that it can be readily distinguished from basement excavations in both its character and substance. As a matter of planning judgement, I therefore find that the development would comprise a single operation which would benefit from the deemed planning permission granted under Article 3 and Class E of Part 1 to Schedule 2 of the Order and that the Council’s decision was not well-founded.”].
• This appeal decision provides an example of where it was concluded that the infilling of a certain volume of earth (or other material) (i.e. as part of other works) does fall within the scope of Part 1 of the GPDO. (*)
  [Note: A “raised plinth or slab” with height up to approx 0.8m would be constructed during the erection of an outbuilding].
  [Quote: “No retaining walls are shown as being proposed, and the only way in which the change in levels is shown as being addressed is through the construction of a raised plinth or slab, which would be at its highest in the north-east corner of the site. [...] In Eatherley, the Court held that the appropriate question to be asked was whether the engineering operations required were a separate activity of substance, and that the assessment was a matter of planning judgement. In my view the construction of a raised base, slab or plinth on sloping ground is a normal part of the construction of a building, and the fact that there would be walls surrounding that base of up to about 0.8m or so in height does not result in it being a separate activity of substance. My views are reinforced by the finding of Cranston J. in Eatherley who commented that “engineering operations for the basement are at some point different in character to those involved in the preparation of foundations for a house”. Here, the construction of the base, plinth or slab is part of the preparations of foundations for the building proposed, and I consider that it can be readily distinguished from basement excavations in both its character and substance. As a matter of planning judgement, I therefore find that the development would comprise a single operation which would benefit from the deemed planning permission granted under Article 3 and Class E of Part 1 to Schedule 2 of the Order and that the Council’s decision was not well-founded.”].

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.