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Appeal Decision 104 - Certificate of Lawful Development.

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March 2010 - Code a00104


Summary of Case (appeal allowed): 


The property is a single storey detached house. The application was for two proposed side extensions (one on each side) and a proposed rear extension, all of which would be separate structures. One of the proposed side extensions would have had width 3.8m, exactly half the width of the main house (7.6m), and the other would have had width 2.7m, less than half the width of the main house. 


The key issue was whether the combined width of the two proposed side extensions 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 phrase “the enlarged part” is clearly a reference back to the opening phrase in Class A itself, namely: “the enlargement … of a dwellinghouse”. So if a certificate were sought for only one of these side extensions, in the absence of any other objection, it would plainly be granted. Put another way, it is the part to be or which has been enlarged that has to be considered, and its width compared to that of the original dwellinghouse. If then a certificate were sought for the second one, it would thus again be the part either to be or which had been enlarged which would fall to be considered, and its width likewise compared with that of the original dwellinghouse.  


The sub-paragraph would not make sense if the two extensions were to be aggregated, whether on separate or simultaneous applications, not least because all of it is written in the singular. Each enlarged part in this case would extend beyond a side wall but neither could extend beyond more than one, nor would either of them extend to the rear of the building or be combined with any rear extension. Each thus falls to be considered individually. If the intention was to restrict the total additional width permitted to half that of the original dwellinghouse, then the Order could, would and should say so. There are indeed other provisions within it which set such overall limits, for example Schedule 2, Part 1, paragraphs A.1(a), B.1(c), D.1(a) and E.1(a), not to mention overall height limits, distance restrictions and the like. The existence of those provisions can only lend support to this interpretation.” 


Main Conclusions: 


·       Where it is proposed to erect two separate side extensions, one on each side of a detached house, then each of these side extensions could have a width up to half the width of the original house (i.e. this limit would not apply to the combined width of the two side extensions).
[Relevant to: A.1(h)].


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


·       Appeal Decision Notice: 

·       OS Map: 

·       Drawings: 





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