Is it a good idea to build an extension on your house?
If you’ve ever asked yourself, “Can I build an extension on my house?” the answer is most likely yes—but there are some key factors to consider before starting the process. As someone with years of experience in construction, I know that the feasibility of building an extension depends on various aspects, such as planning permissions, space availability, and your budget. I’ll walk you through the important considerations to help you decide if you can extend your property and how to approach the process.
Can I Build an Extension Without Planning Permission?
In many cases, you can build an extension without planning permission under permitted development rights. These rights allow homeowners to extend their properties without needing formal approval, as long as the project meets specific criteria.
Permitted Development Criteria
Your extension will likely fall under permitted development if it adheres to these guidelines:
- Size Restrictions:
- Single-storey rear extensions: Must not extend more than 4 metres beyond the rear wall for detached houses or 3 metres for semi-detached or terraced homes.
- Double-storey extensions: Must not extend more than 3 metres beyond the rear wall.
- Height Limitations:
- The extension must not exceed the height of the existing house.
- Single-storey extensions cannot be taller than 4 metres.
- Location Rules:
- Extensions cannot be built forward of the principal elevation (front of the house).
- The project cannot cover more than 50% of the land surrounding the original house.
For a full breakdown of permitted development rights, visit the Planning Portal.
When Planning Permission Is Required
If your extension exceeds permitted development limits or your property falls under special conditions (e.g., a listed building or conservation area), you’ll need to apply for planning permission. You can find detailed guidance on the Gov.uk Planning Permission page.
How Do I Know if I Can Build an Extension on your House?
Before starting an extension project, you need to assess whether your property is suitable. Here’s what to consider:
1. Available Space
The size and layout of your plot will determine whether an extension is feasible. Consider how much garden or outdoor space you’re willing to sacrifice and whether the extension will leave enough room for practical outdoor use.
2. Planning Restrictions
Check if your property is in a conservation area, National Park, or Area of Outstanding Natural Beauty. These locations often have stricter rules, and you’ll likely need planning permission. Additionally, listed buildings have their own set of regulations.
3. Structural Feasibility
Not all properties are structurally suitable for certain types of extensions. For example, older homes may require additional reinforcements to support a second storey or large open-plan areas.
4. Budget
House extensions can range from £20,000 to £100,000+ depending on size, materials, and complexity. Having a clear budget from the start will help determine what’s possible.
5. Building Regulations
Even if your extension doesn’t need planning permission, it must comply with building regulations. These ensure the structural safety, fire safety, and energy efficiency of the project. For a technical guide on building standards, refer to this Government Housing Standards PDF.
Types of Extensions You Can Build
If your property is suitable, there are several types of extensions you can consider:
1. Single-Storey Extensions
Ideal for expanding kitchens, dining rooms, or living areas. These are the most common type of extensions and are typically covered under permitted development.
2. Double-Storey Extensions
Great for adding bedrooms or bathrooms, these extensions maximise vertical space. However, they’re more likely to require planning permission.
3. Side Extensions
Perfect for utilising unused space along the side of your house. Side extensions can create extra storage, utility rooms, or open-plan living areas.
4. Wraparound Extensions
A combination of side and rear extensions, wraparounds significantly increase space and are ideal for creating large open-plan areas.
5. Loft Conversions
While not a ground-level extension, loft conversions are a smart way to add living space without expanding your home’s footprint.
The Process of Building an Extension
Here’s an overview of how to approach the extension process:
1. Check Your Property’s Eligibility
Review permitted development rights and consult with your local planning authority to confirm if you need planning permission.
2. Set a Budget
Outline a realistic budget that includes design, materials, labour, and a contingency for unexpected costs.
3. Create a Design
Work with an architect or designer to create plans that maximise space and functionality while blending seamlessly with your existing property.
4. Hire Professionals
While some tasks can be DIY, I always recommend hiring experienced builders to ensure the work complies with building regulations and meets safety standards.
5. Arrange Inspections
Building control inspections are required at various stages to ensure compliance with regulations. These are mandatory, even for permitted development projects.
Benefits of Building an Extension
If you’re eligible to build an extension, here are some of the benefits:
- Increased Living Space: Extensions can adapt your home to your changing needs, whether it’s for a growing family or a new home office.
- Boosted Property Value: A well-executed extension can add significant value, especially if it includes sought-after features like extra bedrooms or open-plan kitchens.
- Customisation: Extensions allow you to design a space that perfectly suits your lifestyle.
Final Thoughts
In most cases, you can build an extension on your house, provided you comply with planning permissions, building regulations, and structural requirements. Whether it’s a simple single-storey addition or a more complex double-storey project, careful planning is essential to ensure success.
If you’re unsure about the feasibility of building an extension on your property, I’d be happy to help. With years of experience in the construction industry, I can guide you through the process, from initial planning to final completion.
Contact us here to discuss your project. You can also check out our verified reviews on Google My Business and Trust a Trader to see what others say about working with us.
More Blogs
If you found this blog helpful, check out these related blogs that may answer some more questions you have , with Do House Extensions Need Planning Permission? and How Much Do House Extensions Cost in the UK?