Yes, but you will need to obtain planning permission. Converting a detached garage into a self-contained living space, such as annexe, studio flat, or retail unit, represents a material change of use, particularly if it will function independently from the main house. This is because the garage would no longer be used in connection with the main dwelling and would effectively become a separate residential unit.

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.

You don't actually need to own land or property to apply for planning permission for it. This means you can apply for permission before deciding whether or not to buy a piece of land.

The following people must be informed about a planning application relating to land or buildings that they have an interest in:

• The owner or all the part-owner/s (if you are not the full owner)
• Any leaseholders with at least seven years' lease remaining
• Any agricultural tenants.

You can contact your local planning authority for pre-application advice or book an appointment with our Planning Guidance Service.

Find out more about pre-application advice.

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 wall is a 'party wall' if it stands astride the boundary of land belonging to two (or more) different owners, for example the wall separating two semi-detached properties.

Some kinds of work carried out to a property may not be controlled by the building regulations, but may be work which is covered by the Party Wall etc. Act 1996. This is a separate piece of legislation with different requirements to the building regulations.

To find out more about party walls, visit Planning Portal.

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