Green Belt House Extensions

Green Belt House Extensions are an allowable form of development as defined by the National Planning Policy Framework (NPPF) as well as Local Planning Authorities planning policies.

The NPPF provides for “the extension or alteration of a building provided that it does not result in disproportionate additions over and above the size of the original building”.

Generally, we would expect that each LPA green belt house extensions policies would typically dictate a certain percentage over the “original house” often around 15 – 30% either in floor space or volume terms.

The term “original house” is critical in that it means the house as originally constructed or as it stood in 1948. Any extension to the original house would need to be taken into account when investigating further green belt house extensions and in many cases, houses have already had extensions larger than the LPA would allow. As will be highlighted in the following examples, this is not always the end of the options.

Understanding the original house and the scale of previous green belt house extensions is critical as a starting point before any design works are undertaken, however, we are often approached once designs have been produced (or even considered by the Council), still with successful results.

Green Belt House Extensions

The following case studies provide a small sample of green belt house extensions we have been involved with.

Green Belt House Extensions in Cheshire East

Green Belt House Extension in Cheshire East

The detached dormer bungalow had previously been extended past the LPA’s suggested 30% local planning policy, however, our clients weren’t aware of the policies when they purchased the property and still wanted substantial green belt house extensions. Following an initial review, we suggested a planning strategy not only to further extend the house but also to create complimentary outbuildings. The site was quite complex with an irregular shape and substantial level changes. The site was fairly exposed with fantastic panoramic views across Cheshire.

Ultimately we achieved approval for green belt house extensions (not including outbuildings) over 200% larger than the “existing” house but almost 300% larger than the “original” dwelling.

Local Planning Authority: Cheshire East Council

see also: Green Belt; House Extensions; Area of Special County Value

Green Belt House Extensions in Sefton

House Extension in Green Belt in open countryside in Liverpool

Our client’s house sat in open countryside with no immediate neighbours or context but had been previously extended. The configuration of the house and the proximity of the site boundaries created several issues limiting the scale and scope of the green belt house extensions. Working closely with the Council and our clients we obtained planning permission for a contemporary remodelling and extension of the property, including changing the overall appearance of the house and creating a new master bedroom suite. The Council’s policies limited green belt house extensions to a volumetric calculation which created a more complicated planning strategy but ultimately planning approval was granted in excess of planning policies with the LPA commenting: 

“Overall, the scale of the extensions and alterations and the materials used are considered to be in conformity with the existing dwelling. The proposed development would be a more appropriate and sympathetic addition than the alternative options available.”

Local Planning Authority: Sefton Council

see also: Green Belt House Extensions; open countryside; rural developments

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This page provides an introduction only and is not a definitive statement of the law and should therefore not be relied upon.
The information above relates to England only. Policies across the rest of the UK may differ.
Contact your Local Planning Authority for advice and confirmation before any works are carried out.