Permitted development is a planning policy defined by central government to allow homeowners to extend and make changes to their home without going through the full planning process.
What does permitted development mean for my extension?
This means that if your scheme complies with the defined criteria you don’t need to apply for planning permission, but for peace of mind, we would still always recommend applying for a Certificate of Lawful Development prior to commencing works (explained in more detail later).
Permitted development rights don’t apply in the same way if you live in a Conservation Area or National Park. Your local authority will be able to tell you if this is the case.
Permitted development rights are subject to change. The most recent changes came in 31st August 2020.
Permitted development covers a wide range of alterations and extensions, for simplicity we have summarised the criteria below for residential extensions in this post.
General Requirements
The extension can not cover more that half the area of land around the original house (‘original house’ is defined as it first stood or as it stood on the 1st July in 1948).
Where the extension comes within two metres of the boundary, the height at the eaves cannot exceed three metres.
Extensions cannot be built forward of the ‘principal elevation’ or, where it fronts a highway, the ‘side elevation’.
The materials used in any exterior work must be of a similar appearance to those on the exterior of the existing house.
The height of the extension does not exceed the height of the highest part of the roof.
The height of the extension eaves do not exceed the height of the eaves of the existing dwelling house.
Single storey extensions will not exceed 4m in height.
Detached Houses
The extension will not extend the rear wall of the existing house by more than 8m, if the house is detached.
If the extension extends more than 4m from the rear wall of the house, it is categorised as a larger extension, and will be subject to the neighbour consultation scheme (explained in more detail below)
Semi-detached and terraced houses
The extension will not extend the rear wall of the existing house by more than 6m, if the house is detached
If the extension extends more than 3m from the rear wall of the house, it is categorised as a larger extension and subject to the neighbour consultation scheme (explained in more detail below)
Neighbour Consultation Scheme
Neighbourhood consultation scheme - For larger extensions (4m-8m on a detached house and 3m-6m on a semi detached or terraced house), the householder is required to notify the local planning authority to allow them to give notice to adjoining neighbours and give them the opportunity to object.
Fee for of £96 to the local authority.
Decision within 42 days
Side Extensions
Side Extensions are defined as where it would extend beyond the ‘side elevation’ of the original house:
Cannot exceed four metres in height.
Can only be a single storey.
Can only be up-to half the width of the original house*.
Extensions of more than one storey
Rear extensions only.
Must extend less than 3m from the rear wall of the existing house.
Must be more than 7m to the rear boundary.
The roof pitch must match the existing house as far as practicable (note that this also applies to any upper storey built on an existing extension).
Any upper-floor window located in a ‘side elevation’ must be obscure-glazed; and non-opening (unless the openable part is more than 1.7 metres above the floor).
Maximum of up to two storeys and maximum height of 18m.
All side extensions of more than one storey will require householder planning permission.
Certificate of Lawful Development
We would always recommend that the proposals are submitted to the local authority for a Certificate of Lawful Development (to confirm the works are Permitted Development) but providing the government guidelines are adhered to, planning for this type of development is pre-approved. Application for Certificate of Lawful Development is done online through the Planning Portal.
References
Schedule 2 of The Town and Country Planning Order 2015
Part 1 of the General Permitted Development Order 2015 (as amended)
Permitted development rights for householders- Technical Guidance
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