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Appeal Decision 239 - Certificate of Lawful Development.

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May 2011 - Code a00239


Summary of Case (mixed decision): 


The property is a detached house, and the application was for a proposed outbuilding in the rear garden. The proposed outbuilding would be located at least 2m from the boundaries, albeit as a result of a change in the boundary line that was also proposed by this application. The proposed outbuilding would have a crown type roof, with a pitch on either side and a flat area on top (see drawings). The flat roof would be at height 3.95m. 


The key issue was whether the proposed outbuilding would be contrary to Class E, part E.1(d), which states that “Development is not permitted by Class E if … the height of the building, enclosure or container would exceed … (i) 4 metres in the case of a building with a dual-pitched roof, (ii) 2.5 metres in the case of a building, enclosure or container within 2 metres of the boundary of the curtilage of the dwellinghouse, or (iii) 3 metres in any other case”. 


The Inspector stated the following: 


“The central question is whether a roof in which two roof slopes are divided by a flat-roofed element can, for purposes of the GPDO, be described as a dual-pitched roof. Both parties refer to a previous appeal decision (the “Penmarric” decision) which dealt with the definition of a dual-pitched roof in the context of a gambrel roof (a roof with two roof slopes at different angles rising to an apex along the ridge). The Inspector determined that such a roof was not dual-pitched and so, under E.1 of Class E, a height limitation of 3m applied, not 4m. 


The decision does not amount to “case law” as the Council claims because its conclusions have not been tested in the Courts. Nevertheless, it is of relevance to the appeal before me, as a decision that dealt with what might be meant by “dual-pitched roof” as applied to a building for which permitted development rights under Class E of Part 1 were claimed. It is a material consideration to which I attach significant weight. 


The appellant argues that a roof with two roof slopes joined by a flat-roofed element could still be defined as dual-pitched. However, I consider that it is implicit when the term is given its ordinary meaning in everyday language that it refers to a roof with two roof slopes which meet at an apex which forms a single ridge line. There is no definition of the term for purposes of the GPDO which indicates an alternative view. A roof which has side slopes which are divided by a flat roofed element is termed a crown roof, which is a different type of roof form. It is stretching the bounds of everyday language to an unacceptable extent to refer to it as a dual-pitched roof. 


The Government’s technical guidance for householders on the changes to Part 1 introduced in October 2008 is referred to in the Penmarric decision. On p42, it is explained that the 4m height limitation should also be applied to buildings which have hipped roofs. That these are singled out as a variant of “dual-pitched” indicates that what the legislators had in mind was roofs with roof slopes which meet at an apex. This does not include roof slopes with a flatroofed element. The Government could have explained at that juncture that a crown roof could also, in view of the fact that it has two roof slopes, be defined as dual-pitched but it did not do so. 


The underlying logic of the exception made for hipped roofs is that a higher height limit of 4m is intended to apply to roof forms with a less substantial roof mass. By contrast, a gambrel roof or a crown roof in likely to result in a greater presence of roof mass. The building would have a pronounced flat roofed element. The GPDO sets a lower height limit of 3m for such roofs, which would be exceeded by the proposed height of 3.95m. That the Council may have come to a decision more in line with the appellant’s view on a similar proposal is something to which I attach little weight given that it concedes that the Penmarric decision and technical guidance have been issued in the interim. 


Accordingly, I conclude that the proposal would not be lawful as it would exceed the limitations in E.1 whether or not the fence was re-aligned. I do not need to consider whether the enclosure of land by the fence might form part of the curtilage of the appeal dwelling and there is no proposal for a material change of use of the land before me. The Council’s decision to refuse to grant a LDC was well-founded and I conclude that the appeal should fail in so far as it concerns this element. I shall exercise the powers transferred to me in section 195(3) of the 1990 Act accordingly.” 


Main Conclusions: 


·       The phrase “dual-pitched roof” does not apply to an outbuilding with a mansard / crown type roof (i.e. either a roof with shallow pitches in the centre and steeper pitches at the sides, or a roof with a flat area in the centre and pitches at the sides).
[Note: This would appear to contradict at least one other appeal decision – for further information see the entry in the “Reference Section” on “E.1(d)”].
[Relevant to: E.1(d)].


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


·       Appeal Decision Notice: 

·       Drawings: 

·       Costs Decision Notice: 





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