Key point: detached buildings and Green Belt extensions
In Warwick District Council v Secretary of State for Levelling Up, Housing and Communities [2022] EWHC 2145 (Admin), Mr Justice Eyre held that a structure need not be physically attached to an existing building to count as an extension for the purposes of the Green Belt exception then found at paragraph 149(c) of the National Planning Policy Framework. This is not automatic permission for detached outbuildings: the planning decision-maker must consider the individual relationship, including proximity, function, scale and cumulative additions.
Background
The case arose at a Grade II listed cottage in Stoneleigh, Warwickshire, within the Green Belt. Owners wanted to replace a disused detached timber structure, approximately 20 metres from the cottage and with a footprint of 10.2 square metres, with a 16 square metre garden room and home office. Warwick District Council refused permission. An Inspector allowed the ensuing appeal, treating the proposal as an extension associated with the dwelling rather than requiring physical attachment.
The legal issue
Warwick brought a statutory planning review under section 288 of the Town and Country Planning Act 1990. It argued that the word extension necessarily referred to an addition physically joined to the original building. The Secretary of State argued that the policy was not so limited. The court considered the wording in the context of the Green Belt objectives and the requirement that additions must not be disproportionate.
What the High Court decided
Mr Justice Eyre rejected a rigid attachment test. A detached garage or ancillary structure can, on its facts, amount to an extension of another building. The relevant policy test was not an entitlement to permission: decision-makers still needed to consider the entire policy framework and whether the additions were disproportionate. The council’s challenge failed, leaving the Inspector’s grant intact. The judgment expressly recognised that attachment would sometimes be undesirable for listed buildings.
Practical effect
The case assists when evaluating detached garden buildings and ancillary facilities in the Green Belt, but does not mean every freestanding building is an extension. Evidence about original building size, previous enlargement, use, separation and openness remains critical. Nor should the 2022 paragraph number be applied mechanically to the restructured August 2026 Framework. This judgment was subsequently cited in the Broxtowe permitted development conditions appeal. For contemporary advice see Planning Geek’s outbuildings guide.
Judgment: 12th August 2022, Eyre J, CO/820/2022. Public judgment source.
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