Adding a rear extension to your home is a brilliant way to enhance your living space, providing more room and functionality without the need for a costly relocation. Many rear extensions can be completed within permitted development rights, simplifying the process and often eliminating the need for formal planning permission.

In this guide, we’ll explain what permitted development rights are and what you need to follow, and how you can benefit from it.

What is Permitted Development?

Permitted development rights are a set of regulations that allow homeowners to carry out certain types of improvements and additions to their property without needing to apply for planning permission. These rights are designed to streamline straightforward projects, making it quicker and more cost-effective to enhance your home.

For rear extensions, permitted development rights can be particularly helpful as long as your plans meet specific criteria regarding size, height, and design.

Key Rules for Rear Extensions Under Permitted Development

Here are some of the key requirements for rear extensions:

1. Size and Depth of the Extension

The size of your rear extension is one of the most important factors to consider.

• For detached houses – The extension can extend up to 4 meters from the rear wall of the original house.
• For semi-detached or terraced houses – The extension can extend up to 3 meters.

However, if you opt for the larger single-story rear extension, prior approval will be required from your local authority and you may be able to extend further—up to 8 meters for detached houses and 6 meters for other types of properties. It’s important to note that these larger extension limits do not apply to properties located on designated land as deemed by the UK government.

2. Height Restrictions

The height of your rear extension is another important factor under permitted development. The maximum eaves and ridge height cannot be built to be higher than the existing house. Also consider the following height conditions;

• Maximum height –  The extension must not exceed 4 meters in total height for a single-storey rear extension, measured from the lowest ground level of your extension to the highest ridge on your roof.
• Eaves height –  If the extension is within 2 meters of the boundary, the eaves should not exceed 3 meters.

3. Materials and Design

When it comes to the materials used in a rear extension under permitted development, the new structure must complement the existing house. While you have some flexibility in using different types of materials, they should match or blend with the original property’s exterior. This helps maintain the character and visual appeal of the home while ensuring that the extension fits harmoniously within the overall design. Keep in mind that any visible changes to the exterior should not be overly disruptive to the surrounding area or create an imbalance in the property’s overall aesthetic.

4. The Curtilage

Your rear extension cannot take up more than 50% of the land surrounding the original house. This includes any previous extensions, outbuildings and sheds, so it’s important to consider the total land area when planning your extension. If the extension would cover more than this limit, you will need to apply for planning permissions.

5. Location and Restrictions for Designated Land

Certain areas have stricter rules when it comes to permitted development. These are referred to as “designated land”. Therefore, if your home is in one of these areas, you may face restrictions such as smaller extension limits or prohibitions when it comes to certain types of materials used. A few examples of designated land include

• National parks
• Areas of Outstanding Natural Beauty (AONBs)
• Conservation areas

6. No Extensions Facing a Highway

In terms of permitted development, “highways” also refer to footpaths, roads, dual carriageways, motorways etc. Based on these rules, extensions cannot be added to the front or side of a property if they face a public highway. Fortunately, when it comes to rear extensions, this does not apply, as they do not face a highway.

Reasons why you should hire a project management team 

Even though rear extensions under permitted development don’t require planning permission, the process still involves several technical, design and regulatory considerations. That’s where a project management team comes in. A professional team can ensure that your rear extension project runs smoothly from start to finish by;

• Designing a functional and aesthetic extension –  Working with architects and designers to bring your vision to life.
• Managing the construction process – Overseeing the work to ensure it stays on schedule and within budget.
• Ensuring compliance with building regulations –  Ensuring your extension meets all necessary safety and structural standards.

Transform Your Home with Good Design & Build

At Good Design & Build, we specialise in creating stunning rear extensions that fit seamlessly into your home, all while adhering to permitted development regulations. Our expert team is here to help you navigate the complexities of permitted development, ensuring that your extension project is compliant with all necessary legal requirements. Whether you want to extend your kitchen, create a new living space, or add a bedroom, we are here to help you transform your living space. Contact us today to discuss your requirements!