The answer depends on several factors, from size and design to materials and finishes. In this article, we’ll break down the key costs involved, what to expect during the process, and how Standley Design & Build can help you achieve the perfect extension for your home.
Typical Costs of a House Extension in South West London
The cost of a house extension can vary greatly depending on the type of extension you choose. On average, homeowners in South West London can expect the following guide prices:
- Single-storey rear extension: £2,000 – £3,000 per m²
- Double-storey extension: £2,500 – £3,500 per m²
- Side return extension: £2,000 – £2,800 per m²
- Wraparound extension: £2,200 – £3,200 per m²
These figures are a starting point and don’t include finishes, fixtures, or bespoke design features, which can significantly influence the final price.
Factors That Influence Extension Costs
Several variables affect the overall cost of a South West London house extension.
1. Size and Complexity
Larger extensions naturally cost more, but complexity also plays a role. A simple rear extension will cost less than a multi-storey, wraparound design with complex structural requirements.
2. Type of Extension
Different styles of extensions come with different costs. For example, a loft conversion in Wimbledon may be more cost-effective than a full two-storey extension in Kingston, depending on the existing structure.
3. Materials and Finishes
The choice of brickwork, roofing, flooring, and windows can make a big difference. Premium materials such as aluminium bi-fold doors or natural stone flooring will increase costs but also add long-term value.
4. Planning and Regulations
Some projects may fall under permitted development rights, while others require planning permission from the local authority. In areas such as Surbiton or Raynes Park, planning constraints may impact the overall design and cost.
5. Design Features
Open-plan layouts, bespoke kitchens, roof lanterns, or underfloor heating can all elevate the final cost but transform the usability and feel of the space.
House Extensions in South West London: Area Insights
As specialists in the region, Standley Design & Build understands the character and requirements of homes across South West London.
- Wimbledon: Known for its period homes, Wimbledon often requires sympathetic extensions that blend traditional architecture with modern functionality.
- Kingston: With a mix of riverside properties and family homes, Kingston offers opportunities for larger double-storey extensions.
- New Malden: Popular with families, many homeowners opt for open-plan kitchen extensions to create more living space.
- Raynes Park: Semi-detached homes in this area benefit from side return or wraparound extensions to maximise space without losing garden area.
- Surbiton: Characterised by Victorian and Edwardian homes, extensions here often focus on retaining period charm while adding contemporary touches.
- Worcester Park: With larger plots, Worcester Park properties are well-suited to rear and side extensions, offering excellent potential for value growth.
Value for Money
While the upfront cost of a house extension can seem significant, it’s important to view it as an investment. A well-designed and professionally built extension can add substantial value to your home—sometimes up to 20–25% depending on the location and quality of finish. In areas such as Wimbledon, Kingston, and Surbiton, where demand for spacious family homes is strong, an extension can significantly boost property appeal and resale value.
Why Choose Standley Design & Build?
At Standley Design & Build, we take pride in delivering bespoke extensions that enhance both lifestyle and property value.
- Bespoke Design: Every project is tailored to suit your property, needs, and budget.
- Expert Knowledge: We understand South West London homes, from Victorian terraces to modern builds.
- Full Service: From planning and design through to construction and finishing touches, we manage the entire process.
- High Standards: Our skilled craftsmen use premium materials and pay close attention to detail, ensuring lasting quality.
- Trusted Team: With years of experience, we’ve built a strong reputation across Wimbledon, Kingston, New Malden, Raynes Park, Surbiton, and Worcester Park.
Planning Your Extension
If you’re considering a house extension in South West London, here’s how to get started:
- Initial Consultation: Discuss your goals, budget, and ideas with our team.
- Design Development: We’ll create layouts that maximise space and style.
- Planning & Permissions: We handle applications and ensure compliance with local regulations.
- Build & Installation: Our experienced builders bring the design to life with precision.
- Finishing Touches: From kitchens to flooring, we deliver a complete, ready-to-use space.
Standley Design & Builds Final Thoughts
So, how much does a house extension cost in South West London? The answer depends on size, style, and finishes—but with expert guidance from Standley Design & Build, you’ll get a solution that perfectly balances cost, quality, and long-term value.
Whether you’re in Wimbledon, Kingston, New Malden, Raynes Park, Surbiton, or Worcester Park, our team is here to create extensions that transform your home and lifestyle.
Contact Standley Design & Build today to arrange a consultation and discover how we can bring your extension plans to life.