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Appeal Decision 174 - Certificate of Lawful Development.

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December 2010 - Code a00174


Summary of Case (appeal dismissed): 


The property is a large detached house, to the side of which there is an existing detached double garage. The latter structure was erected in the 1980s, and replaced an original detached garage. The application was for various works including a proposed “link” extension that would join the side wall of the main house to the side wall of the existing garage, as well as alterations to the existing double garage itself. 


The width of the “link” extension by itself would not exceed half the width of the original house. However, the width of the combined structure consisting of the “link” extension and the altered outbuilding would exceed half the width of the original house. 


The key issue was whether the proposals would be contrary to Class A, part A.1(h), which states that “Development is not permitted by Class A if … the enlarged part of the dwellinghouse would extend beyond a wall forming a side elevation of the original dwellinghouse, and would— … (iii) have a width greater than half the width of the original dwellinghouse”. 


The Inspector stated the following: 


“The appellant disagrees with the Council’s interpretation of Class A of Schedule 2, Part 1 of the GPDO as amended in 2008 and in particular with the interpretation of paragraph A.1 (h) (iii). He considers that the small link building is permitted development under Part A and, in his view, the garage permission is entirely separate and is not relevant in assessing whether the enlarged part of the house would have a greater width than half the width of the original dwelling. He relies on the Explanatory Memorandum to the 2008 amendment to support his approach pointing out that one permitted development does not prevent or count against a second. However, a distinction can only be made in circumstances where there are two or more clearly severable elements, in which case rights may be claimed for one or the other if on its own it meets the requirements of the GPDO and was not carried out as one larger development. I agree with the Council’s interpretation that by virtue of the link extension, the conversion and alterations to the existing garage become part of the proposed enlargement of the dwelling as they form inseparable elements of the same development. 



I recognise that the development would not exceed 4m in height and not have more than one storey thereby not breaching the criteria in paragraph A.1 (h) (i) and (ii). However the enlargement resulting from the link extension and the conversion of the garage would be greater than half the width of the original dwelling, irrespective of whether the appellant’s or the Council’s calculations are relied upon, and therefore would not be permitted development under paragraph A.1 (h) (iii) of the GPDO”. 


The Inspector also concluded that the width of the original detached garage should not be taken into consideration when calculating the “width of the original dwellinghouse”. 


[Note: My first instinct with this appeal decision was to write a conclusion along the following lines: 


“This appeal decision states, or implies, that the phrase “the enlarged part of the dwellinghouse” not only applies to the proposed extension, but also includes any non-original outbuilding to which the proposed extension would be attached”. 


However, upon re-reading the appeal decision notice, I am unsure whether the Inspector’s conclusion (i.e. that the width of the combined structure should be measured) would have also applied if the link extension had been proposed without the separate alterations to the existing outbuilding (other than the alteration necessary to join the two structures). As such, I have not stated any conclusions for this appeal decision]. 


Main Conclusions: 


·       No conclusions (see my comments above) 


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


·       Appeal Decision Notice: 






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