Loft
Expertise.
We are Loft Conversion experts in South West London. Fee free to contact us for a free quote
Get Free QuoteExtension
Specialist.
Enhance your lifestyle at home with extended property. Our specialist is here to help you.
Contact UsInterior
Design Works.
Our design creates spheres of architecture i.e. planning, building regulation, project management, building work services, interiors
Get StartedCommercial
Fit-Outs
For any refurbishments, interior fit-outs, or shop fittings, We can customise the space to the needs of your business.
Contact UsLoft Conversions
The perfect way to gain extra living space, be it an extra bedroom with an en-suite, or a games room; converting your loft is a cost-effective way to create some much-needed additional space in your home.
+House Extensions
We offer extensions that are of the highest quality in terms of design, craftsmanship, and sustainability. Our work will not only give you additional space but will enhance both your property and your lifestyle.
+New Builds & Basement
From bespoke new build homes to basement conversions, we manage every stage of your project. Our team delivers exceptional craftsmanship, energy-efficient designs, and modern living spaces tailored to your vision.
+Interior & Refurbishment
We complete your project with a stunning interior. Our interior team create beautiful spaces for residential and commercial clients - from full home refurbishments to bespoke kitchen and bathroom design.
+Commercial Fit Outs
We transform commercial spaces for offices, retail units, restaurants, and hospitality businesses. Our commercial team handles everything from initial concept through to fit-out and snagging.
+London's Trusted Extension & Loft Conversion Specialists
BuildExtensions has been transforming homes and commercial spaces across London and Surrey since 2010. Based in Raynes Park, we combine expert craftsmanship with full architectural and planning support — giving our clients a genuinely stress-free build experience.
We're a design-and-build company, which means you get a single point of contact from initial planning drawings through to project completion. No subcontractor confusion, no budget surprises.
Over 100 completed projects. Hundreds of satisfied clients. And a reputation built entirely on recommendation.
More About Us
Years Experience
Complete Work
Happy Customers
Years Experience
Company Member
What makes us different?
We don't just build. We plan, design, manage the build, and hand over a finished project. Every client gets a named project manager from day one. Every project is covered by full structural and building regulation sign-off.
We specialise in residential loft conversions and house extensions, and our commercial team handles office refurbishments, shop fit-outs, and restaurant interior works across London.
Whether you're adding a bedroom, converting a loft, building an extension, or transforming a commercial space - BuildExtensions delivers projects on time, on budget, and to an exceptional standard.
Our Core Values
Loft Conversions
House Extensions
New Builds & Basement
Interior & Refurbishment
Commercial Fit Outs
Our Complete Project
New build House
Cobham Surrey UK
New Build House
Windlesham Surrey
Interior & Refurbishment
Henley-On-Thames
Extension & Full Refurbishment
Banstead
Side Extension
Epsom & Ewell
Restaurant design
Kingston-Upon-Thames
Why Choose Us
- Over 20 years delivering Loft conversions and Extensions in South West London
- Full design-and-build service: one team, one point of contact, zero confusion
- In-house architectural drawings and planning permission support
- All projects fully covered by building regulations and structural sign-off
- Transparent pricing — detailed quotes with no hidden costs
- Free initial consultation for all residential and commercial projects
- Trusted by homeowners and delivers projects on time, on budget, and to an exceptional standard
What Our Clients Say
BuildExtensions transformed our cramped loft into a stunning master bedroom with en-suite. The team was professional from start to finish, and they completed the project two weeks ahead of schedule. We could not be happier with the quality of workmanship.
Sarah Mitchell
Homeowner, Wimbledon
We needed a rear kitchen extension and full ground floor refurbishment. BuildExtensions handled everything from planning permission to the final paint touch-ups. Our project manager kept us informed every step of the way. The result exceeded our expectations.
James & Rebecca Hartley
Homeowners, Richmond
The commercial fit-out team delivered our restaurant refurbishment on time and within budget. They understood our vision perfectly and worked around our business hours to minimise disruption. The space looks incredible and our customers love it.
David Chen
Restaurant Owner, Kingston
Interested in Our Services?
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