Appeal against a refusal of planning permission for the retention of a rear conservatory extension

Appeal Allowed (Retrospective Planning Permission Granted) on 23 April 2024


90 Wimborne Avenue,

Council: London Borough of Hillingdon

We get lots of enquiries from people who have built an extension believing it to be permitted development (and therefore not needing planning permission at all), only to discover that it does not quite comply with the permitted development rules in some way and that they are at risk of enforcement action.

In this case, our client built a conservatory at the back assuming it was permitted development because it was less than 3 metres deep. However, because it was attached to a pre-existing ground floor extension, the homeowner had already used up their permitted development entitlement.

She had applied for retrospective planning permission for the extension but had been refused by Hillingdon council and therefore faced the prospect of having to demolish the structure.

We appealed against the refusal of planning permission, arguing that the conservatory was a modest and lightweight structure and that it did not rise very much above the side boundary fences. 

The inspector agreed with us that the impact of the conservatory would be so great that there would be any harm to the neighbours to either side.

Our client was very relieved when retrospective planning permission was granted. 

If you have been refused planning permission or are facing planning enforcement action (and especially if you have been served with an Enforcement Notice), please do not hesitate to contact our chartered town planners for some advice.

Also check out the book How to Get Planning Permission for in-depth, insider advice on extensions, appeals, permitted development and planning enforcement.

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