Anstey Horne

Daylight Error Fatal to Planning Permission

Rights of light Case Summary

The High Court has found that a daylight error was fatal to the grant of planning permission.

The Court quashed the permission for a mixed use development likely to adversely affect daylight reaching a neighbouring school’s playground due to an error of fact.

The developer had commissioned Twenty16 Design (T16 Design) to assess how much of the playground would be in shadow if the proposal went ahead. In the computer model created for the assessment, a fence was drawn around the playground in place of a two-metre brick wall, understating by a third the effect of the new scheme on the playground.

In Watt v London Borough of Hackney the judge confirmed that the error of fact justified quashing the permission. An independent assessment of the daylight found that the amount reaching the play area was above the relevant policy threshold, but not as far above as the original assessment had, wrongly, suggested.

Despite the fact that the daylight error may not have been decisive in the overall decision, the judge was prepared to quash the permission. This judgement confirms the risk that faulty technical work creates for planning decisions, even where the error itself is not decisive.


For further information or advice on Daylight & Sunlight please contact :

Rebecca Chapman


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