Q: Class A.1 (h) (iii), part 1, schedule 2 of the October 2008 amendments to the General Permitted Development Order 1995 states that a side extension to a house is not permitted development if its width would be greater than half the width of the original dwellinghouse. The Department for Communities and Local Government's August 2010 technical guidance is silent on whether a "half width" extension on each side of a detached house on a large plot would be permitted, thus doubling its width. I do not think that this can be the order's intention, but I would be grateful for your views. KZ

A: In an appeal decision from May 2009 (

), an inspector states: "I agree with the appellant that in addition to a rear extension, the existing dwelling could also be extended on both sides." Although the appeal was dismissed for other reasons, the council accepted this entitlement in negotiating an acceptable alternative scheme. John Anderson

A: A recent appeal decision (

) seems to indicate clearly that both sides of a detached house can be extended as permitted development. Stephen Hayhurst

A: Class A.1 (h) effectively states that development is not permitted if "the enlarged part of the dwellinghouse would extend beyond a wall forming a side elevation of the original dwellinghouse and would have a width greater than half the width of the original dwellinghouse". There is no qualification restricting extensions to one side only, so it seems they are permitted on both sides. While this could harm planning objectives, such as in green belts where retaining openness is important, such extensions can only be prevented by an article 4 direction withdrawing permitted development rights. John Harrison


Next Questions

It has been put to us that if a planning application is submitted for the demolition of an existing building in a conservation area and its replacement by a new building, there is no need for the applicant to submit a separate application for conservation area consent for the demolition because this is covered by the planning application. I cannot find anything in the legislation to support this view. We would welcome clarification. RA

An application was submitted by a tenant of the premises involved. A new owner then bought the property and lodged an appeal against refusal of the application. Section 78(1) of the Town and Country Planning Act 1990 states that only "the applicant" may appeal. I can find no legislative provision that allows the transfer of appeal rights. Is there scope for judicial review here? CN

Do you have an answer to these questions? If so, please email it to Forum editor John Harrison at by 23 November. We also welcome your queries, which can be emailed to the same address.


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