A - I do not believe there is power to "invalidate" an application. If an authority decides that it has incorrectly validated an application, this does not mean that it is "invalidating" it but rather that it was never properly validated. The authority should either have returned your application and fee so that you could start again or given you a set time to supply an acceptable plan so that it could correctly validate the application, at which point the clock would restart. Paul Barkley
Q - What are your views as to whether public defribrillators need planning permission? PD
A - Your response (Planning, 6 November, p22) that defibrillators do not need planning permission is incorrect where a unit is placed in a cabinet screwed to the outside of a building and has an electrical supply to provide heating in cold conditions. Such a cabinet is likely to require planning permission. In many cases, the answer may be for a local authority, such as a district or parish council, to install it, in which case it would be permitted development. Bruce Barnett
Q - My neighbours put in a planning application for front and rear dormers. This was rejected and they submitted a planning application just for front dormers, which was then approved. They then applied for a lawful development certificate for rear dormers with no front dormers. The total volume was 49.97 cubic metres and the application was approved. Work is now starting and comprises front and rear dormers. The dormers' combined volume will exceed 50 cubic metres. Would this make the certificate and permission invalid? RW
Q - My house is in a conservation area covered by an article 4 direction removing permitted development rights for proposals facing a highway, waterway or open space. I made a lawful development certificate application for a rear extension backing onto a park, which was granted. I then received an email from the council stating that the application was wrongly decided and the certificate should not be used, requesting confirmation within three days that I would not rely on it. Can it revoke the certificate in this way? AS
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