Appeal Decision 130 - Certificate of Lawful Development.

August 2010 - Code a00130

Summary of Case (appeal allowed): 

The property is a two-storey mid-terrace house, with an original two-storey rear projection. The application was for a proposed “L”-shaped dormer, which would have been across both the rear roof of the main part of the house as well as the side roof of the original two-storey rear projection.  

The Council first reason for refusal was on the basis that “the element of the proposed rear dormer to be sited on the roof of the two storey rear projection is not part of the roof structure and therefore is not considered to constitute Permitted Development under Article 3 and Schedule 2, Part 1, Class B …”. As such, the first key issue was whether the part of the proposed dormer on the roof of the original rear projection would fall within the scope of Class B.  

The Inspector stated the following: 

“My understanding of advice from the Communities and Local Government on the Planning Portal [reference to “DCLG - Permitted development for householders - Technical guidance” (August 2010)], which has been published since the Council’s refusal decision, is that this type of rear addition ‘outrigger’ roof extension is allowed under Class B and classed as a roof extension.” 

The second key issue was whether the part of the proposed dormer on the roof of the original rear projection (noting that this dormer would have a flat roof that would be higher than the ridge-line of the latter) would be contrary to Class B, part B.1(a), which states that “Development is not permitted by Class B if … any part of the dwellinghouse would, as a result of the works, exceed the height of the highest part of the existing roof”. 

The Inspector stated the following: 

“Under Class B on page 32 [of the “DCLG - Permitted development for householders - Technical guidance” (August 2010)] it is stated: “The highest part of the roof of the existing dwelling house will be the height of the ridge line of the main roof (even though there may be other ridge lines at a lower level) or the height of the highest roof where roofs on a building are flat.” Additions or alterations to any part of the dwellinghouse may therefore involve more than one part of the roof, the test being that “no part of the house once enlarged exceeds the height of the highest part of the roof of the existing house”. 

… 

“Class B of Part 1 of Schedule 2 to the GPDO provides that development in the form of enlargement of a dwellinghouse consisting of an addition or alteration to its roof is permitted development subject to certain exceptions and conditions as set out in B.1 and B.2. The roof of a dwellinghouse is not defined by the Order and its ordinary meaning should therefore be used, that is the covering that forms the top of the building. It is clear from the plans and elevations that both the rear main roof and the outrigger roof will be added to and extended by the proposal. Reference to the application and the accompanying drawing ref: NP/0901 seems to me to show conclusively that the proposal is for additions and alterations to the roof of [the application site] and should therefore be considered under Class B.” 

As the eaves of the original two-storey rear projection are at a lower level than the eaves of the main rear roof, the part where the dormer extends from the former roof to the latter roof would involve removing a section of the original eaves of the main rear roof. The third key issue was whether this 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 stated the following: 

“As regards the claim that the development would not comply with conditions at B.2 (b) and (c), the rear extension passes over the eaves; but the GDPO says that it must be 20cm as far as practical and at the point the roof extends between the main roof and the outrigger any overhang is not practical.” 

“I now turn to the conditions in B.2 to which the Council have drawn attention in reasons 2 and 3 of their decision. Reason 2 states that the proposed rear dormer is not inset from the eaves by a minimum of 20cm and is therefore not permitted under B.2 (b). However, B.2 (b) states that “…the edge of the enlargement closest to the eaves of the original roof shall, as far as practicable, be not less than 20 centimetres from the eaves of the original roof...”. The condition contains the words “as far as practical”. The part of the proposed development that extends across the rear roof slope would join onto the outrigger in one continuous, stepped, extension. The latter extension is set back from the eaves of the sloping roof but it is clearly impractical for the adjoining extension on the main roof to stop 20 cm from the eaves of the rear roof slope. Such a design would result in two discrete and separate extensions requiring two sets of internal stairs, a clearly impractical solution. The CLG advice on the Planning Portal, referred to above, states under Condition B.2 (b): “One circumstance where it will not prove practical to maintain this 20cm distance will be where a dormer on a side extension of a house joins an existing, or proposed, dormer on the main roof of the house.” Therefore, the Council have no sustainable case here. I conclude that the proposal does not breach condition B.2 (b) as set out in the amended GPDO.” 

Main Conclusions: 

·       Where a property has an original rear projection (with a roof at a similar level to the main roof) then an extension (e.g. a dormer) on the roof of the original rear projection would fall within the scope of Class B (i.e. rather than Class A).
[Note: This would appear to contradict at least one other appeal decision – for further information see the entry in the “Reference Section” on “Interaction between Class A, Class B, and Class C”].
[Relevant to: “Interaction between Class A, Class B, and Class C”, Class A, A.1(i), Class B, B.1(c)].

·       The phrase “the highest part of the existing roof” refers to the house as a whole (i.e. the main ridge-line), and not just the part of the house where the works would be carried out.
[Note: This would appear to contradict at least one other appeal decision – for further information see the entry in the “Reference Section” on “Highest Part of the … Roof”].
[Relevant to: “Highest Part of the … Roof”, A.1(b), C.1(b), G.1(a), H.1(b)].

·       For example, where a property has an original rear projection, a dormer on the roof of the latter structure is limited by the height of the main ridge-line of the house, and not by the height of the ridge-line of the original rear projection.
[Note: This would appear to contradict at least one other appeal decision – for further information see the entry in the “Reference Section” on “Highest Part of the … Roof”].
[Relevant to: “Highest Part of the … Roof”, A.1(b), B.1(a), C.1(b), G.1(a), H.1(b)].

 

·       Where the eaves of an original two-storey rear projection are at a lower level than the eaves of the main rear roof, the requirement to be not less than 20cm from the eaves of the original roof would not prevent an “L”-shaped dormer that extends from the former roof to the latter roof.
[Relevant to: B.2(b)].

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

·       Appeal Decision Notice:
http://planningjungle.com/?s2member_file_download=a00130-Appeal-Decision-Notice.pdf&s2member_skip_confirmation&s2member_file_inline=yes 

·       Drawings:
http://planningjungle.com/?s2member_file_download=a00130-Drawings.pdf&s2member_skip_confirmation&s2member_file_inline=yes 

Download documents and diagrams of useful

Permitted Development information