Planning Permission for the Conversion of Buildings in the Green Belt
Thinking of converting a barn or other building in the Green Belt? Learn how re-use proposals can qualify as exceptions to inappropriate development.
GREEN BELT
Andrew Ransome
6/28/20263 min read
The conversion and re-use of existing buildings is one of the most commercially significant exceptions to inappropriate development in the Green Belt.
For owners of redundant buildings in the Green Belt, it can provide a route to new residential, leisure or commercial uses without the need to demonstrate very special circumstances.
This article sets out the tests and the practical implications for projects in involving the conversion and re-use of existing buildings in the Green Belt.
NPPF: Paragraph 154(h)(iv)
Paragraph 154(h)(iv) of the NPPF explains that the re-use of buildings is not inappropriate development in the Green Belt, provided:
the buildings are of permanent and substantial construction,
the development preserves the openness of the Green Belt, and
the development does not conflict with the purposes of including land within it.
Permanent and Substantial Construction
The requirement for permanent and substantial construction filters out temporary, lightweight or structurally degraded buildings not capable of genuine conversion without essentially being rebuilt.
A timber-framed polytunnel, a heavily deteriorated structure with no meaningful remaining fabric, or a prefabricated temporary building will not satisfy this test.
Applicants are often expected to demonstrate — typically through a structural survey — that the building could be converted rather than demolished and rebuilt.
Where a scheme described as re-use in reality involves demolishing the structure and constructing a new building, the correct analysis is whether the proposal falls within the replacement building exception under paragraph 154(d) rather than the re-use exception.
Preservation of Openness
The openness test for re-use proposals is not simply a question of whether the building's footprint or volume changes.
It extends to domestic paraphernalia, car parking, fencing, garden areas and changes to the associated land that inevitably accompany a residential re-use.
In Smith v Secretary of State for Communities and Local Government [2017], the High Court confirmed that there was no legal error by the Inspector in finding that proposed fencing, bin storage, car parking and domestic paraphernalia associated with a residential conversion would fail to preserve openness.
In Baynham v Secretary of State for Communities and Local Government and East Hertfordshire District Council [2017], the judge endorsed an Inspector's approach to openness in the context of residential re-use — the question is simply whether the character of the use introduced is urban in nature and whether that harms openness.
Residential re-use is consistently the most difficult category to satisfy the openness test. Domestic uses generate associated development — garden enclosures, surfaced areas, domestic outbuildings — that can sometimes be judged to increase urban development.
Extensions Alongside Re-use
Where a proposal involves re-use together with extensions or alterations, the extension must be separately assessed under paragraph 154(c).
The extension must not result in disproportionate additions over and above the size of the original building.
Both the re-use tests and the extension test must be satisfied independently.
A modest re-use of a barn together with a small extension may therefore need to satisfy the openness test (under re-use) and the proportionality test (under the extension exception) simultaneously.
Class Q and the Re-use Exception
Agricultural buildings can in many cases be converted to residential use under Class Q of the GPDO, subject to prior approval.
Class Q rights do not engage Green Belt policy directly — permitted development operates by granting planning permission automatically without a Green Belt assessment.
The relationship between Class Q and the re-use exception becomes relevant where an applicant seeks a full planning permission for a conversion going beyond what Class Q would permit, using the Class Q prior approval as a fallback.
Re-use of Buildings in the Green Belt: Summary
The re-use of permanent and substantial buildings under paragraph 154(h)(iv) provides a recognised route through the Green Belt, but carries an express openness test applied strictly.
Planning Application Advice
If you own land or a building in the Green Belt and want to understand your development options, I can advise on planning strategy and manage your application from initial assessment through to decision. Contact me to discuss your site.
Andrew Ransome MRTPI - Email: andrew@andrewransome.co.uk
About me
Andrew Ransome is a Planning Director and a Chartered Member of the Royal Town Planning Institute (RTPI), with more than two decades of experience in town planning.
He specialises in delivering strategic planning solutions for complex developments across both rural and urban environments, helping clients navigate planning challenges and unlock development opportunities. Connect with Andrew on Linkedin.
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Get in touch for planning advice: Email: andrew@andrewransome.co.uk
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