Creating a new basement will usually require planning permission, particularly if it affects the external appearance of the property. For example, installing a lightwell to bring natural light into the basement may be subject to stricter design rules if it is visible from the street, especially at the front of the property, compared to those at the rear or side.

Because basement construction involves significant excavation and structural work, permission is often necessary. It’s recommended that you consult your local planning authority early on to understand what is likely to be considered acceptable before submitting a planning application. Building regulations will also apply to a new or conversion of a basement.

Read further guidance on basements.

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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Whether you need planning permission to install an extractor fan depends on the size and placement of the fan.

For domestic installations, such as a bathroom or kitchen in your house, planning permission is not generally required. If the change significantly alters the external appearance of your home then permission may be required.

If you live in a listed building, you will need listed building consent for any significant changes.

Larger extractor fans for businesses are likely to require an application for planning permission to be made to the local planning authority. These extractors can impact the local area due to their noise, visibility and odour, as such the planning authority will need to assess the change.

Building regulations relating to ventilation and electrical works will have to be complied with, these are covered by Approved Document F and P respectively.

Read more about building regulations and the requirement for ventilation on our common projects.

Significant changes to insulation and thermal elements would normally require building regulations approval. The extent to which this applies depends on the existing insulation and what it will be replaced with.

If the work is completed by a member of a competent persons scheme, then an application for approval will not be required.

Find out more about insulation and building regulations on our common projects.

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If the garage will remain in domestic use - for example, as a personal hobby or home workshop - then planning permission is typically not required.  

However, it’s important to check whether there are any planning conditions, covenants, or restrictions attached to your property or the garage itself that may limit or prevent conversion.  

Read about planning permission for garage conversions on Planning Portal.  

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