Casebook: Development Control Casebook Forum

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Alternatively, post them to Development Control Casebook Forum, Development Control Services Ltd, Suite 1, Fullers Court, 40 Lower Quay Street, Gloucester GL1 2LW or fax them to 01978 869355.


Opinion is divided at my authority on whether security shutters fitted behind a shop window need permission but seems to turn on whether these "materially affect the external appearance of the building". What is your view? PO.

In Burroughs Day v Bristol City Council (1996) it was held that when applying such a test it is the "external appearance" of a building that must be affected and not just the "exterior". It therefore follows that something that can be seen through a window may have a material effect on external appearance.

However, in an appeal from Newport in 1999, it was thought that an "internal" shutter behind a shop window did not materially affect appearance (DCS No: 36086573). The inspector felt that whether the shutter was development in the first place and, if it was, whether it had a material effect on external appearance were "arguable issues" that were not clear cut. But as he found that the works had no material effect, he concluded that they were not development. PM.

I am dealing with an application for a lawful development certificate for a small mobile shed, which I am satisfied is an article and not a structure. Logically, I cannot say that it is "lawful development" as I do not think that it is development. Therefore I must refuse the application.

But in doing so I will disappoint the applicant, who only wants to know whether he is liable to enforcement and is not interested in such subtle distinctions. Is it possible to grant a certificate of lawfulness for something that is not development? PL.

Section 191(2) of the Town and Country Planning Act 1990 states that existing uses and operations are lawful at any time if, among other things, no enforcement action may be taken in respect of them "because they did not involve development". While there is no similar provision under section 192, which deals with applications for a proposed use or development, it is clear that the approach is the same.

Annex 8 to Circular 10/97, which sets out related guidance, lists nine categories of development or "other activity" on land that is lawful for planning purposes, including that which is not within the definition of "development". The annex also advises that in deciding applications under section 192, the planning authority's consideration should include whether the proposal would involve "development" requiring an application for planning permission. Appeal cases support this approach and demonstrate that inspectors have frequently granted certificates in the circumstances you describe. PM.

I am appealing against an authority's decision to refuse an application for a lawful development certificate for an area of land that was originally used as a car park for employees of a village mill. In its response, the authority has used the terms "sui generis" and "subsisting use". Are these expressions defined? YC.

Sui generis is not defined in planning legislation but is a legal term which means "of its own kind". Where it is used in a planning context, it indicates that a use is outside the scope of any of the classes set out in the Use Classes Order 1987. It will therefore not qualify for the rights given to uses falling within those classes. Neither is "subsisting use" defined. However, this is simply another way of saying that a use continues to exist. PM.


In reply to HG's query about access to flat roofs for recreational purposes (Planning, 26 November, p25), PM stated that "openings or replacement windows that have been inserted to facilitate the use of the roof could be considered to have a material effect on the external appearance of the dwelling and would thus require permission".

Section 55(2)(a)(ii) of the 1990 act states that works that materially affect the external appearance of a building are development that would require permission. However, the point is overlooked that, subject to compliance with the limitations under class A, part 1, schedule 2 of the General Permitted Development Order 1995, windows and other alterations and improvements are permitted development. None of these limitations refers to material effect on the external appearance of the dwellinghouse.

This approach is confirmed by appendix D to Circular 9/95, which refers to windows as development that it may be important to control under an article 4 direction, and by the government's booklet Planning: A Guide for Householders. The impression should not be given that the material effect on the external appearance of a dwellinghouse can be controlled in the way PM suggests. However, it is open to authorities to remove such rights by condition when permitting extensions. CC.

Other readers have made similar points and I accept that this part of my reply was unclear. However, the phrase quoted by CC is preceded by the words "possible" and "unauthorised". I had in mind the type of circumstances that arose in an enforcement appeal from the Forest of Dean in 1999 (DCS No: 39129190).

Here the inspector held that a door at first-floor level to a recently-built extension providing access to a flat roof was clearly a building operation that materially affected the external appearance of the building.

As the door was not authorised by the permission for the extension, it represented a breach of control and constituted development for which permission was needed. The inspector upheld the enforcement notice, concluding that while the use of the flat roof did not involve a material change of use, as overlooking problems would not arise without the door, the door was objectionable.

CC correctly summarises the approach to windows to single dwellinghouses and this is consistent with my earlier reply to the similar query raised by KM (Planning, 30 July, p21). Such permitted development rights do not of course apply where a building is divided into flats. PM.

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