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.

To qualify as permitted development some household building work projects – notably extending a house – must not exceed limits to the volume being added.  

In England, the volume allowance mostly applies to loft conversions. You can read more on the Planning Portal. 

Use the volume calculator to find out the volume of several loft conversion and extension types.

Removing a non-load bearing wall will likely not require building control approval provided it does not affect fire escape routes, ventilation, drainage or electrics.

It is best practice to get a report from a structural engineer to ensure the wall is non-load bearing prior to starting any work.

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If your proposal for planning permission or building regulations approval is solely for extensions or alterations to a disabled person’s house to improve access, safety or comfort then you are exempt from paying a planning or building control fee. Additionally, if you are providing means of access for disabled persons to public buildings you are exempt from any fee.

Note that for building regulations approval, you will only be exempt when applying to a local authority building control body.

Adding air conditioning to your home may be considered permitted development provided all the limits and conditions set out in legislation are met. The limits set out the function, size, placement and quantity of air conditioning units allowed.

The rights only apply if the system provides a heating function (including if it can provide both heating and cooling). If the system only offers a cooling function, then the rights do not apply and an application for planning permission will be required.

If your home is in a protected area such as a Conservation Area then permission will be required. If you live in a listed building then consent will be required.

The installation of air conditioning must comply with building regulations. It is advisable to contact an installer who can provide the necessary advice, preferably one who belongs to either the Microgeneration Certification Scheme or the relevant Competent Person Scheme.

For more information on air conditioning, read our heat pumps common project.

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