If you plan to put up a small, detached building like a garden shed, garden room, garden office, annexe or summerhouse (all classed as outbuildings), building regulations generally won’t apply if the building has a floor area under 15 square metres and does not include any sleeping accommodation.

For buildings with a floor area between 15 and 30 square metres, building regulations approval is usually not needed - as long as the building does not include sleeping accommodation and either:

• it is at least one metre away from any boundary, or
• it is built mainly from non-combustible materials.

Read more about the building regulations that apply to outbuildings.

Don't forget to check the permitted development rights for outbuildings.

‍

Two storey rear extensions are considered to be permitted development, meaning they do not require an application for planning permission provided certain limits and conditions are met. If these limits are exceeded then you will need to apply for planning permission from the local planning authority.

Houses on designated land such as national parks or conservation areas are excluded from the permitted development rights and will require an application for planning permission.

To fall within permitted development rights, the extension should be no higher than the existing house, and where it is within two metres of a boundary, the eaves should be no higher than three metres. 

Any double storey extension to the side or front of the house will require planning permission. You can view the full limits and conditions on our Two-storey extension Mini Guide.

If you live in a listed building you will require listed building consent for any major works to the property.

Your planning application must be made up of:

• The necessary plans of the site
• The required supporting documentation
• The completed form
• The correct fee.

The local planning authority will not be able to process your application unless the mandatory supporting documentation has been provided. You can also attach any other relevant documentation which you think will help the local authority determine the application.

What supporting documentation must be provided depends on the application type,  development type and local planning authority.

There are two levels of mandatory documents, national and local. If you’re applying online, the service will tell you what mandatory documentation you need to provide and allows you to attach the relevant documents. Most applications will require you to provide a location plan and a site plan.

In addition to the national list, your LPA may produce a list which details any specific documentation that is required to accompany the application. The requirements may vary according to the type of application, i.e. household, full, outline, etc. If you are applying online, this list is available from the supporting documents screen or your local planning authority’s website.

For more information around what to submit visit the how to apply section on Planning Portal.

A council’s planning department, known as the local planning authority (LPA), is the local government body responsible for managing and overseeing the planning system in a specific area.

You can use the search tool on Planning Portal to find the contact details for any local planning authority in England and Wales.

Find your local planning authority.

In many cases, you can extend a house without applying for planning permission by using what's known as permitted development rights, provided certain limits and conditions are met. However, if your plans go beyond these restrictions, you will likely need to apply for householder planning permission.

Read guidance on extensions.

See our extensions MiniGuide.