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Appeal Decision 223 - Certificate of Lawful Development.

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


March 2011 - Code a00223


Summary of Case (appeal dismissed): 


The property is a two-storey semi-detached house with a hipped main roof. The property has previously been extended with a two-storey side extension. The hipped roof of the extension joins onto the main hipped roof, albeit with the ridge-line of the former at a lower level than the ridge-line of the latter. The application proposed to convert the hipped end of the main roof (part of which covered by the attached roof of the extension) into a gable end, to erect a large rear dormer, and to convert the half-hipped end of the two-storey side extension into a gable end. 


The key issue was whether the proposed enlargement of the roof would be contrary to Class B, part B.1(c), which states that “Development is not permitted by Class B if … the cubic content of the resulting roof space would exceed the cubic content of the original roof space by more than— (i) 40 cubic metres in the case of a terrace house, or (ii) 50 cubic metres in any other case”. 


The Inspector stated the following: 


“The appellant’s drawings, prepared by professional agents, show the existing building and proposed alterations, including a schedule of the dimensions to calculate the volume of the work. Council officers have made their own calculation of the volume of the work at 56.90 m3. Further, although the appellant’s agent says that the total volume of new building work to the roof is 49.22 m3, the actual net addition of the volumes set out in the schedule is 54.88 m3. 


Overall, I agree with the Council that the work described on the submitted plans exceeds the 50 m3 limitation specified in the GPDO. I therefore conclude on the evidence submitted that the appellant has not proved, on the balance of probabilities, that the proposed work is ‘permitted development’.” 


[Note: Where there is an existing extension with a roof that joins onto the roof of the main house, in other appeals the key question has been whether this existing extension will reduce the volume allowance that remains for roof extensions under Class B, part B.1(c). However, in this particular appeal, because the appeal decision notice is relatively short, I am unable to tell how the Inspector has interpreted this issue].


Main Conclusions: 


·       No conclusions (see above note). 


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


·       Appeal Decision Notice: 

·       Drawings: 




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