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Appeal Decision 121 - Certificate of Lawful Development.

This appeal decision summary and assessment has been produced by Planning Jungle Limited.  For more information, please go to



June 2010 - Code a00121  


Summary of Case (appeal dismissed): 


The property is a two-storey semi-detached house with an original two-storey rear projection.  Directly to the rear of the latter structure, there is an existing single storey rear extension.  The application would have removed the latter extension, and would have erected a large outbuilding detached from the rear wall of the original two-storey rear projection by just 5cm.  The outbuilding would have covered the full width of the site, and would have had length 8m.  An inward-opening door in the rear elevation of the original two-storey rear projection would have been within very close proximity to an inward-opening door in the outbuilding, allowing direct access between the two structures, although no part of the two structures would touch.  Please see the submitted drawings for further information. 


The key issue was whether a structure in such close proximity to the main house would fall under Class A, which relates to “The enlargement, improvement or other alteration of a dwellinghouse”, or under Class E, which relates to “The provision within the curtilage of the dwellinghouse of … any building …”. 


The Inspector stated the following: 


“The Council has argued that because of the building’s very close proximity to the existing dwelling it cannot be regarded as a separate structure, but more properly as an enlargement of the existing dwelling which would fall to be considered under Class A of Part 1 of Schedule 2. If so regarded, the building would not be permitted under Class A because it would extend beyond the rear wall of the original dwelling house by more than 3 metres (Class A.1 (e)). 


Before October 2008, any curtilage building of more than 10 cubic metres constructed within 5 metres of the existing dwelling would have been treated as an enlargement of the dwellinghouse and so considered under  Class A. That limitation was explicitly removed from the GPDO amendments which came into force in October 2008. The submitted drawing of the proposed building clearly and unambiguously shows that no part of the new building would contact the existing building and it would be completely detached from the main dwelling. Under these circumstances, I consider that despite its proximity to the dwellinghouse the building would be a separate structure within the curtilage and not an enlargement of the dwelling. It therefore falls to be considered under Class E because it involves “the provision within the curtilage of the dwellinghouse of... any building...”. 


[Note: In my opinion, one of the major flaws of the amended version of Part 1 is that it no longer includes an Interpretation that any detached structure within 5m should be treated as a Class A extension (rather than a Class E outbuilding).  As a result, there is now the potential to circumvent the rear projection limits of Class A (which are designed to protect neighbour amenity) and the side projection limits of Class A (which are designed to protect the streetscene) by erecting a detached structure within close proximity to the main house (i.e. instead of an attached structure). 


However, I am not particularly convinced by the argument that just because this Interpretation has now been removed, it therefore follows that there is no limit whatsoever to how close a detached structure can be to the main house whilst still falling under Class E.  In my opinion, a 5cm separation distance is clearly a “token” amount, and if the structure subject of this appeal were built (please see the submitted drawings via the link below), an average person viewing it would be far more likely to identify it as “an extension” rather than “an outbuilding”.  In any case, as this is the only appeal decision so far that has dealt with this particular issue, in my opinion LPAs would be entitled to continue to form their own interpretations of this particular issue until further guidance or appeal decisions become available]. 


The Inspector then dismissed the appeal on the basis that the applicant had failed to demonstrate that the proposed outbuilding would be “incidental to the enjoyment of the dwellinghouse”. 


Main Conclusions: 


·       Even if a detached structure would be separated from the main house by only a very small (i.e. token) amount, this would still be sufficient for the structure to fall under Class E (“the provision within the curtilage of the dwellinghouse of … any building …”) rather than Class A (“the enlargement, improvement or other alteration of a dwellinghouse”).
[Relevant to: “Interaction between Class A and Class E”, Class A, Class E]. 


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


·       Appeal Decision Notice: 

·       OS Map: 

·       Drawings: 





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