Is planning permission required to sub-divide a building?

Is planning permission required to sub-divide a building?

Planning permission may not be required to sub-divide a building where:

• sub-division does not involve physical works that amount to development;
• the use of any newly formed units after a building has been sub-divided falls within the same use class as the building’s existing primary use before it was sub-divided, or there is a permitted development right allowing the new use; and/or
• the sub-division does not involve converting a single dwelling house to contain more than one residential unit.

Subdividing a building into multiple units can be an appealing option for property owners looking to maximize rental income or make better use of their habitable space. However, whether you need planning permission for such a project depends on several factors, including the building's location, its current use, and the extent of the proposed changes.

In most cases, subdividing a building will require planning permission. This is because creating separate units typically changes the building's use class and is considered “development” which requires permission by law. For example, converting a single-family home into multiple flats or turning a commercial property into residential units usually involves a change of use that planning laws must approve.

The necessity of planning permission also hinges on the building's existing use class. If the building is a house (Class C3) and you plan to convert it into multiple dwellings, such as flats, planning permission is almost always required. Similarly, converting a commercial building (e.g., Class E) into residential flats will also require planning approval. However, there are some exceptions under Permitted Development Rights (PD Rights). For instance, certain types of buildings, like offices, can be converted into residential units without full planning permission under specific conditions, although prior approval from the local authority is still necessary and certain information needs to be considered (noise, size, pollution, flooding & impact on the high street / highway if applicable and parking).

Another critical factor is the local planning policies of the council where the building is located. Some councils may have stricter regulations, particularly in conservation areas or listed buildings, where additional constraints are placed on changes to the property. Moreover, even if your subdivision falls under permitted development rights, you may still need to apply for building regulations approval to ensure that the new units meet safety and habitability standards, including fire safety, sound insulation, and access.

In summary, while some subdivisions might be allowed under permitted development, most will require formal full planning permission. Before proceeding with any subdivision project, it is essential to consult with your local planning authority or seek professional advice from 4D Planning to ensure compliance with all relevant regulations and to avoid potential legal issues down the line.

Is the property listed?

The way to check if your property is listed is to visit the Historic England website and search their map with your post code. If the property is listed you will require the Council's permission for all internal alterations. Listed Building Consent is required and the Conservation and Heritage Officers would inspect the property and assess the impact of the proposed works on the significance of the heritage asset. The listing of a property relates to the interior as well as the exterior even if the property was never inspected or surveyed by Historic England (English Heritage) at the time of the listing.

4D Planning have over a decade of experience working on projects in Listed Buildings. These include refurbishments of Grade II listed homes, replacement of windows, new layouts and extensions to listed properties. Each project is unique and has its own character and features.

For further information, please contact us to speak to our specialist heritage and conservation consultant.