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Appeal Decision 28 - Certificate of Lawful Development.

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September 2009 - Code a00028


Summary of Case (appeal dismissed): 


The property is a three-storey mid-terrace house, and the application was for a basement extension under the full width and length of the rear garden. The roof of the basement would have been at ground level (not projecting above the latter), such that brick paving directly on top of this roof would have formed the new surface of the rear garden.

The Inspector noted that Class A (which permits “The enlargement, improvement or other alteration of a dwellinghouse”) does not specifically mention basements, but stated that this does not in itself imply that basements are not permitted development. He stated that, in his view, basements do fall within the scope of Class A, and are therefore permitted development only if they do not infringe any of the limitations of the Class.

The Inspector then looked specifically at part A.1(e), which states that “development is not permitted by Class A if … the enlarged part of the dwellinghouse would … extend beyond the rear wall of the original dwellinghouse by more than … 3 metres”. The Inspector concluded that this 3m projection limit does apply to basements and that therefore the proposed basement, which would project further than this, would not be permitted development.

The Inspector also looked at part A.1(a), which relates to “the total area of ground covered by buildings within the curtilage of the dwellinghouse”. He noted that t
he roof of the proposed basement would form the new surface of the rear garden and that, whilst this surface would be no higher than the existing garden level, none of the original ground would remain. However, he concluded that it would be rather “contrived” to regard that the proposed basement would increase the area of ground covered by buildings.

However, the Inspector then noted that the creation of the proposed basement would
require the excavation of a substantial amount of material from across almost the entire rear garden, which would constitute an “engineering operation”. He states that there is nothing in the GPDO to indicate that such an operation is permitted development.

[Note: In my opinion, this appeal decision is questionable, because it appears to first imply that basements do fall within Class A, and then imply that basements do not fall within the GPDO. In my opinion, the excavation of earth and the subsequent construction of a room below ground level form one process, namely “the creation of a basement”. As such, if it is considered that this process, “the creation of a basement”, falls under the Class A phrase “the enlargement … of a dwellinghouse”, and is not contrary to any of the limitations or conditions or that Class, then this process would be “permitted development”. This would imply that the whole process, consisting of all of its integral parts, could be undertaken without planning permission. It appears irrelevant to then make a distinction as to whether each integral part of such a process is “development” in the first place by virtue of being a “building” operation (for example the construction of a room) or an “engineering” operation (for example the excavation of earth), as the GPDO does not make such a distinction].


Main Conclusions: 


·       Although this appeal decision deals with the question of whether basements fall within Class A, in my opinion it is questionable, because it appears to first imply that basements do fall within Class A, and then imply that basements do not fall within the GPDO.
[Relevant to: “Basements”].


·       The 3m/4m rear projection limit of Class A, part A.1(e) does apply to basements. This implies that the projection limits of Class A, parts A.1(d), A.1(f), A.1(h), A.2(b), and A.2(c) would also apply to basements.
[Relevant to: “Basements”, A.1(d), A.1(e), A.1(f), A.1(h), A.2(b), A.2(c)].


Links to the “Appeal Decision Notice” and other associated documents (e.g. drawings, etc): 


·       Appeal Decision Notice: 

·       Existing Elevations and Section: 

·       Proposed Elevations and Section: 

·       Proposed Floor Plans: 






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