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Appeal Decision 42 - Certificate of Lawful Development.

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

November 2009 - Code a00042


Summary of Case (mixed decisions): 


The property is a two-storey end-of-terrace house, with an original single storey rear projection, on top of which a first floor rear extension (with a flat roof) has subsequently been added. The application was for a proposed rear dormer with a door leading to a roof terrace on top of the existing first floor rear extension, and two outbuildings in the rear garden. One of the differences between the two applications (and two appeals) was that the two outbuildings were described as a “home office” and “orangery” in Appeal A, but an “outbuilding” (i.e. for an unspecified purpose) and “orangery” in Appeal B. 


The first key issue was whether the proposed rear dormer would be contrary to Class B, part B.2(b), which states that “other than in the case of a hip-to-gable enlargement, the edge of the enlargement closest to the eaves of the original roof shall, so far as practicable, be not less than 20 centimetres from the eaves of the original roof”.


The Inspector noted that the proposed rear dormer would be built straight up on top of the main rear wall, and that one of the submitted drawings showed that this would give a set-back of 20cm from the eaves, with a strip of projecting eaves remaining. However, he also noted that some of the other submitted drawings indicated that at least part of this strip of projecting eaves would be removed, such that the rear dormer would rise straight up from the main rear wall without any interruption. The Inspector concluded that in order for the proposals to comply with Class B, part B.2(b), there would need to remain “a continuous 20cm strip of roof slope”. 


The Inspector noted that “the onus of proof in a LDC application is firmly on the applicant”, and concluded that this part of the appeals should be dismissed on the basis that the applicant had not shown that the proposals would comply with Class B, part B.2(b). 


Main Conclusions: 


·       In order for a dormer extension to comply with Class B, part B.2(b), there needs to remain a continuous strip of at least 20cm of original roof slope below the base of the dormer. It is not possible to comply with this condition by saying that the dormer would be set-back 20cm from the notional point where the original eaves would have been when the latter has been removed.
[Note: This would appear to contradict at least one other appeal decision – for further information see the entry in the “Reference Section” on “B.2(b)”].
[Relevant to: B.2(b)].


·       Where an applicant submits contradictory information (for example, where one drawing indicates that a particular limitation or condition would be met, but another drawing indicates that the same limitation or condition would not be met) then the application should be refused.
[Relevant to: “General”].


·       In an application for a certificate of lawfulness, the burden of proof is firmly on the applicant.
[Relevant to: "General”].


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


·       Appeal Decision Notice: 

·       OS Map: 

·       Existing Front, Rear and Side Elevations: 

·       Proposed Floor Plans and Section: 

·       Proposed Front and Rear Elevations: 

·       Proposed Side Elevations: 






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