One of the first questions homeowners ask when considering an extension is whether they need planning permission. The answer depends on several factors, including the size and type of extension, your property's location, and its current use.
What is Permitted Development?
Permitted Development (PD) rights are a set of rules that allow certain types of development without the need for full planning permission. These rights apply to most residential properties in England, subject to specific conditions and limits.
For house extensions, PD rights typically allow:
- Single storey rear extensions up to 4 metres for detached houses, or 3 metres for other properties
- Single storey side extensions up to half the width of the original property
- Extensions that don't exceed 50% of the total area of land around the original house
When You Don't Need Planning Permission
Under permitted development rules, you may not need planning permission if:
- Your extension falls within the size limits specified above
- The extension doesn't exceed the height of your existing roof
- No part of the extension extends beyond the front or side elevation that faces a road
- Materials used are similar in appearance to the existing property
- The extension doesn't create a separate dwelling
However, even when PD applies, you must still comply with Building Regulations, which ensure the work meets safety and structural standards.
When You Do Need Planning Permission
You will need full planning permission if:
- Your extension exceeds the permitted development limits
- You live in a flat or maisonette (PD rights are more restricted)
- Your property is a listed building (even minor changes require listed building consent)
- The extension is within a conservation area or national park
- You want to extend forward of the front elevation
- The extension would have a significant impact on neighboring properties
Conservation Areas and Designated Lands
Properties in conservation areas, Areas of Outstanding Natural Beauty, or national parks have significantly reduced permitted development rights. In these locations, even small extensions may require planning permission.
If your property is listed, you will almost certainly need both planning permission and listed building consent for any extension work. This applies even to internal alterations that affect the character of the building.
Prior Approval
For certain larger single storey extensions, you can use a "prior approval" process. This is a faster procedure where the council only checks specific matters like neighbor impact, rather than full planning merits. The process typically takes 5 weeks and costs £96.
The Importance of a Lawful Development Certificate
Even if you believe your extension falls within permitted development, it's wise to apply for a Lawful Development Certificate (LDC). This legal document confirms that your extension is lawful and can be invaluable when selling your property or for peace of mind.
How We Can Help
At Doherty Builders, we have extensive experience navigating the planning process. We can advise whether your extension requires planning permission, assist with architectural drawings, and handle the application process on your behalf.
Contact us today to discuss your project and we'll guide you through the planning requirements.