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Building On Green Belt – Planning & NPPF


NPPF Green Belt – The National Planning Policy Framework (NPPF) sets out the guidance and rules relating to the green belt land. Consequently this is a particular issue for house extensions and replacement dwellings

The NPPF (National Planning Policy Framework) states that “The Government attaches great importance to Green Belts land. The fundamental aim of Green Belt policy is to prevent urban sprawl by keeping land permanently open. The essential characteristics of Green Belts are their openness and their permanence.”

Green Belt Replacement Home The NPPF states that the five purposes of the Green Belt are:

– To check the unrestricted sprawl of large built-up areas.
– To prevent neighbouring towns merging into one another.
– To assist in safeguarding the countryside from encroachment.
– To preserve the setting and special character of historic towns.
– To assist in urban regeneration, by encouraging the recycling of derelict and other urban land.

Paragraph 143 states that “Inappropriate development is, by definition, harmful to the Green Belt and should not be approved except in very special circumstances.” The document elaborates that new buildings on green belt are inappropriate unless they fall within a limited number of exceptions.

Green Belt House Extensions and Home Remodelling

Unpicking the guidance and using creative thinking to create modern family homes

For house extensions to existing properties within the Green Belt the NPPF states that “the extension or alteration of a building” is allowable “… provided that it does not result in disproportionate additions over and above the size of the original building”. In planning terms the keywords are “disproportionate” and “original”.

It is suggested that different local planning authorities (LPA’s) deal with the term “disproportionate” in different ways when interpreting Green Belt land or open countryside policies and the specific LPA policies need to reviewed and understood however as a typical guide a figure of 30% increase in floorspace from the original dwelling is not uncommon. Other LPA’s will consider footprint, external rather than internal floorspace or volume among other things as starting points when considering house extensions in the green belt.

In planning terms, the “original” dwelling means the building as it stood before the introduction of the Planning Act on 1st July 1948. Any later extensions (whether by planning approval or permitted development may not be included. In some cases, we have found that houses have already been extended past the allowable figure meaning, in theory, that the planning officers wouldn’t accept any further house extensions within the green belt or open countryside.

For more information on planning permission for Green Belt House Extensions across the UK, with projects up to 300% increase, please look at our dedicated page, which features numerous Case Studies or contact us

Self Build Homes, Bespoke New Build & Replacement Dwellings in Green Belt


The best of both worlds – Creating a new home in a beautiful rural setting?

For all new homes, including replacement dwellings, there are generally 5 main options within open countryside or Green Belt as stated in the NPPF:

– the replacement of a building, provided the new building is in the same use and not materially larger than the one it replaces.

– limited infilling in villages, and limited affordable housing for local community needs under policies set out in the Local Plan. or

– limited infilling, or the partial or complete redevelopment of previously developed sites (brownfield land), whether redundant or in continuing use (excluding temporary buildings), which would not have a greater impact on the openness of the Green Belt and the purpose of including land within it than the existing development.

In addition, there may be possibilities for:

– The conversion of existing buildings in open countryside; for more information please see Barn Conversions.

– Creating bespoke homes that meet the exceptional quality or innovative in nature requirements of Paragraph 80 (Formerly Paragraphs 55 and 79) of the NPPF to satisfy the “very special circumstances” caveat. For more information please see our dedicated page.

The infilling of site or redevelopment of brownfield sites in the green belt or open countryside are very site-specific. A detailed review and analysis would be required to ascertain the issues, possibilities and opportunities.

When looking at replacement dwellings, one of the key planning terms is materially larger. In addition, the starting point is typically the size of the existing rather than original home. This potentially provides some additional scope from extensions within the green belt. As with house extensions, a starting point for a replacement dwelling in green belt is the internal floorspace. However external footprint, volume, scale and massing and character of the area are all factors to be considered.

Similarly to extensions to houses in the green belt, in our experience different LPA’s have different approaches and requirements when planning for new houses in the green belt. Typically though we have found new replacement homes proposing over a 15% increase from the existing dwelling is seen as being materially larger. Elements such as double-height spaces, basements, permitted development, outbuildings, garden rooms etc. can add further complication to the issues.

For more information on green belt planning permission for New Homes, across the UK, please look at our dedicated page, with numerous Case Studies, on our sister website or contact us.

Green Belt Replacement Dwelling House
Green Belt House Extension
Green Belt Planning

Hunter Architects are Expert in Green Belt Planning for Homes across the UK

Green Belt planning can provide a fantastic opportunity to create functional and efficient homes set in beautiful countryside

Across the geographical areas that Hunter Architects work, a large proportion of projects fall within open countryside and Green Belt. This is particular of south Manchester and the northern half of the Cheshire East Council area. This includes around many of the most affluent areas of Wilmslow, Alderley Edge, Knutsford, Macclesfield, Prestbury etc.

Hunter Architects & Planners have been involved with many challenging house extension and replacement dwelling projects within open countryside and particularly Green Belt. By way of two brief examples:

For new build bespoke homes in the green belt, we have previously obtained approval for a replacement dwelling which in its original configuration was only around 70 sq m. The house had been extended to around 90 sq m meaning it had been extended as much as the LPA would allow. Ultimately we obtained approval for a house of around 240 sq m. (A 266% increase from existing and substantially more than the 15% the LPA initially considered acceptable). There was also the potential for further house extensions to this dwelling once completed, taking the total house past 300 sq m.

For house extensions in the green belt, we have been involved with many projects ranging from 50% to over 300% increase from the “original house”.

Please note that the above comments are given as a simplistic overview of green belt issues and should not be treated as specific advice. There is a plethora of case law that evolves and clarifies the issues including the various planning terms. These terms include  “materially larger” and “disproportionate”. Expert assistance should be sought at the earliest opportunity. Please Contact us to discuss your Green Belt house extension or replacement dwelling project or for any enquiries relating to homes in open countryside.

Commercial & Residential RTPI Planning Consultancy Services across the UK

This website is dedicated to residential and bespoke domestic projects, however, we have a wide range of experience obtaining planning permission for a wide range of sites and across different sectors.

If you are a developer, land-owner, business, private client, Architect and/ or designer looking to achieve approval or submit an appeal for a site or building, across the UK, please have a look at our sister website - Plande.

Please contact us to discuss your particular project, needs and issues.

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