Method’s Quick Guide to Single Storey Extensions
Have you been dreaming about that much needed space or a new home extension? Maybe you want to know what’s allowed under Permitted Development (PD) law? For more information on loft conversions and first floor extensions under permitted development read some of our previous articles. This article is a brief guide to single storey extensions and tips for what’s allowed under permitted development. But first things first, what do we mean by permitted development?
What can be considered as Permitted Development?
For an extension or addition to your house to be considered as permitted development (not requiring an application for planning permission) certain limits and conditions must be met. It’s always best to check with your Local Planning Authority whether permitted development rights apply. It’s also important to bear in mind that other consents may be required if your house is listed or in a designated area like green belt or conservation. The permitted development allowances in this article apply to houses only and not flats, maisonettes or other buildings. Here are a few of the basic requirements to meet permitted development regulations:
Regulations:
If your house is on ‘designated land’ (see below) extensions cannot be more than one storey, there can be no side extensions or cladding of the exterior.
No more than half the area of land around the 'original house’ (see below) can be covered by additions or other buildings. Sheds and other outbuildings must be included when calculating this limit.
Side extensions can be only single storey, have a maximum height of four metres and the width cannot be more than half the width of the original house.
If the extension is within two metres of a boundary the maximum eaves height cannot be higher than three metres.
Single-storey rear extensions must not extend beyond the rear wall of the original house by more than four meters if a detached house, or more than three meters for any other house. If the house is not on ’designated land’ or a Site of Special Scientific Interest, this limit is increased to eight metres if a detached house, or six metres for any other house but this would be subject to ‘prior approval’ (see below).
The maximum highest point of a single-storey rear extension is only four metres and the maximum eaves and ridge height of an extension must be no higher than the existing house.
You cannot extend forward if you are facing a road.
Materials must be similar in appearance to the existing house.
Key expressions:
Designated land - National Parks and the Broads, Areas of Outstanding Natural Beauty, Conservation Areas and World Heritage Sites. Please read our news article for more information.
Original house - the house as it was first built or as it stood on 1 July 1948, if it was built before then. Keep in mind that you may not have built an extension to the house but a previous owner might have.
Prior approval - Approval from the local planning authority for specified elements of a project that are acceptable and must be approved before work can proceed.
These are just some of the basic requirements and information to get you started. If you’re still not sure what to do next with your extension project give the team at Method Studio a call. We have years of experience dealing with permitted development extensions. Here’s an example of one of our previous jobs to give you an idea of the high quality designs we have created under PD.