Do I need planning permission for an extension?

Planning permission for extension

Thanks to ‘permitted’ development, not all extensions require the homeowner to acquire planning permission – speeding up the whole process and cutting out administration costs. We take you through the requirements…

Back in 2015, the government introduced updated householder permitted development rights, in a bid to speed up the planning process and stop local authorities’ planning departments getting clogged up with straightforward planning permission applications. Permitted development rights already existed allowing certain alterations and extensions, but these revisions increased the scope of development that did not require householders to submit applications to Councils seeking planning permission.

The permitted development rights, conveyed by the Town and Country Planning (General Permitted Development) (England) Order 2015 (as amended), Schedule 2, Part 1, allows the erection of a single-storey extension without the need for planning permission, presuming amongst others the following criteria can be satisfied:

  1. Does not extend beyond a wall which forms the principal elevation of the original property, or fronts a highway and forms a side elevation of the original house
  2. Is constructed with exterior materials that are similar to the original house
  3. If it comes to within 2m of a property boundary, the eaves must be no higher than 3m and it must be no more than 4m high
  4. A rear extension must be not more than 4m in depth for a detached house and 3m for a semi or terraced house, although until 30th May 2019 subject to other requirements it is possible for the dimension to be 8m and 6m respectively
  5. If you are planning a side extension it must be no more than half as wide as the original building
  6. For certain extensions the property should not be located within an Area of Outstanding Natural Beauty or Conservation Area

Two-storey extensions

You can also add two-storey extensions at the rear of your property under permitted development. It must adhere to the following restrictions:

  1. It must be 3m or less deep
  2. It cannot be closer than 7m to your rear boundaries
  3. There will also be restrictions regarding glazed windows in such extensions, to avoid neighbouring properties being overlooked

If any of these apply to your two-storey extension – you WILL need planning permission:

  1. If it covers more than half the land that surrounds your property
  2. If it will extend towards a road
  3. If the eaves are taller than those of the original property
  4. If it is to be located on the side of the house and exceeds 4 m in height
  5. If it is more than half the width of the original house

Whilst the permitted development rights allow for development that will not be the subject of a planning application and the subjective opinion of Council planning officers and third-party consultees, it should be noted from the above that there remain various criteria that must still be satisfied. It should also be recognised that those listed above present a flavour of the issues for one to consider and is not intended to represent the full list.

It is highly recommended than anyone considering an extension should obtain the advice of a qualified person, which could be an architect or a planning consultant, or to pay for pre-application advice from the Council. Permitted development rights are complex and involve a lot of cross referencing, meaning that while they could allow one to avoid the application process they are not necessarily straight forward.

It should also be noted that if you propose a single storey extension that is up to 6m or 8m in depth (see point 4 above) this is possible until 30th May 2019. However, it is necessary to submit what is often termed a ‘light-touch’ application to the Council, providing prior notification of the works and meeting specific information requirements to ascertain whether its prior approval is required.  One stipulation is that the works must be completed by 30th May 2019.

Building regulations

While you may be able to build an extension without applying for planning permission in the instances we have outlined above, remember that the requirement for Building Regulations approval is a separate matter beyond the permitted development rights discussed above, and the planning application process.

You may find a contractor who is building control certified, otherwise you will need to contact the local planning authority’s own building control department. You will need to apply showing your plans and they will send someone out to inspect the work. Often your builder will liaise with building control once you have made the initial application.

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