Cost of Home Extensions in Surbiton and Surrounding Areas: A Complete Breakdown
8 January 2025

A home extension is one of the best ways to increase your living space, enhance your property’s value, and improve your quality of life. However, understanding the costs involved is crucial before you start your project. At Home Improvement & Construction Limited (HICL), we specialise in delivering bespoke home extensions across Surbiton, Kingston, Wimbledon, Teddington, and nearby areas.


This guide breaks down the key factors influencing the cost of home extensions and offers insights to help you budget effectively.

HICL insights - 5 - Cost of Home Extensions in Surbiton and Surrounding Areas: A Complete Breakdown


1.  Average Cost of Home Extensions in Surbiton


The cost of a home extension can vary widely based on the size, type, and complexity of the project. Here’s a general breakdown:


  • Single-Storey Extensions: Typically start at £37,000 - depending on materials and finishes.
  • Double-Storey Extensions: Typically start at £85,000 - offering more space for less cost per square metre compared to single-storey options.
  • Kitchen Extensions: Costs start at around £12,000.
  • Loft Conversions: Start at £25,000 - providing additional bedrooms or office space.


For a detailed, tailored quote, contact our team for a free consultation.



2.  Factors Affecting Extension Costs


Several variables can influence the final cost of your home extension:

1. Size and Layout

The size of the extension is the most significant factor. Larger extensions naturally require more materials and labour, increasing the overall cost. Complex layouts or multi-functional spaces can also raise expenses.


2. Materials and Finishes

The choice of materials plays a significant role in determining costs. High-end materials like bespoke glazing, hardwood flooring, or premium kitchen fittings will increase your budget compared to standard options.


3. Type of Extension

Different types of extensions have varying cost implications. For example, a side return extension in Surbiton may be more cost-effective than a rear extension in Kingston that requires significant groundwork.


4. Planning and Permissions

Obtaining planning permission and adhering to local regulations may involve additional costs, especially in conservation areas like Richmond or Wimbledon. Learn more about the planning process in our blog: Planning Permissions for Extensions in Surbiton: What You Need to Know.


5. Labour and Professional Services

Hiring experienced extension builders and architects is essential for quality results. At HICL, we provide end-to-end construction services to ensure your project runs smoothly.



We can help you! Come visit us; just pop in for a coffee or call us on 020 83397955.



3.  Cost-Saving Tips for Your Extension


  1. Choose Cost-Effective Materials: Opt for durable but affordable materials to stay within budget.
  2. Plan for Energy Efficiency: Energy-efficient designs can reduce long-term operational costs.
  3. Work with Local Builders: Partnering with local experts like HICL ensures familiarity with suppliers and regulations in areas like Twickenham, Cobham, and Woking.



To provide a complete perspective, here are some specific cost considerations based on areas HICL serves:


  • Affordable home extensions in New Malden: This area often allows for simpler builds, making costs more manageable.
  • Luxury house extensions in Oxshott: High-end finishes and materials can raise the price but elevate the property’s appeal.
  • Garage conversions in Leatherhead: Converting unused garages into functional spaces is a cost-effective alternative to traditional extensions.
  • Kitchen expansion projects in Raynes Park: Popular for families, these projects often require customised solutions.


4.  Why Choose HICL for Your Extension?


At Home Improvement & Construction Limited, we pride ourselves on delivering value-driven extensions that meet your needs and budget. Serving Surbiton, KT5, KT6, and surrounding areas, we offer:

     - Comprehensive project management

     - Transparent pricing with no hidden costs

     - High-quality craftsmanship tailored to your vision




Get Started Today with Home Improvement & Construction Limited


Ready to transform your home? Discover innovative extension ideas in our blog: Top 7 Home Extension Ideas to Maximise Space in Your Surbiton Property.


Contact HICL today for a no-obligation consultation and let us bring your dream extension to life. Serving South-West London, we’re here to help you every step of the way.




Like what you see? Reach out to our experienced team, located in Surbiton.



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