At Thames Design & Build, we have been delivering residential design and construction services across South West London and Surrey since 2011. Founded by Rob Allison, we work throughout Kingston, Thames Ditton, Esher, Molesey, Walton-on-Thames, Cobham, Oxshott, Wimbledon, Richmond, Epsom, Leatherhead, Twickenham, Sheen, Kew, Dorking, Guildford and neighbouring areas. Our business is built on a combination of architectural knowledge and practical building expertise, enabling us to undertake home extensions, loft conversions and structural alterations with confidence and care. Whether our clients approach us with completed plans or the earliest ideas for their property, we provide clear guidance at every stage of the process.
We offer a complete design and build service, bringing architectural drawings, planning applications, construction and project management together under one roof. By integrating design and delivery, we help remove the challenges often associated with appointing separate architects and contractors. Our team includes qualified designers, project managers and experienced tradespeople, including Gas Safe registered plumbers and ECA registered electricians. From rear, kitchen, side return and wraparound extensions to garage conversions, two-storey additions and full house renovations, we create practical homes designed to support everyday living.
We offer a complete design and build service, bringing architectural drawings, planning applications, construction and project management together under one roof. By integrating design and delivery, we help remove the challenges often associated with appointing separate architects and contractors. Our team includes qualified designers, project managers and experienced tradespeople, including Gas Safe registered plumbers and ECA registered electricians. From rear, kitchen, side return and wraparound extensions to garage conversions, two-storey additions and full house renovations, we create practical homes designed to support everyday living.
Served areas
- Kingston Upon Thames, Thames Ditton, Esher, Molesey, Walton-on-Thames, Weybridge, Cobham, Oxshott, Wimbledon, Richmond, Epsom, Leatherhead, Twickenham, Sheen, Kew, Dorking, Guildford
Details
- Year established: 2011
- Employees: 20
Highlights and features
- Residential design and build specialists across London Surrey
- Complete extensions conversions and refurbishment solutions delivered
- Architectural expertise combined with hands-on building experience
- Qualified designers managers and skilled tradespeople included
- Planning approvals and construction managed from start finish
- Trusted local service for homeowners transforming properties
Payment methods
- Bank transfers
Services
Thames Design & Build Ltd provides homeowners with comprehensive support for their property improvements. Our services include extensions, loft conversions, renovations, and bespoke architectural designs. We are committed to delivering excellent craftsmanship throughout every project. With planning, design, and construction under one roof, we create functional and refined living environments. 
Through our rear extension service, we guide homeowners from their first ideas to final completion. We begin by reviewing your requirements and determining the available options for your property. Our team prepares the necessary documentation and manages construction throughout. The completed space is designed to blend effortlessly with the existing home. 
A kitchen extension can significantly improve how you use your home, creating a more open and inviting living space. We guide you through each phase of the project, from the earliest ideas to final completion. Our team coordinates every aspect of the works. Clear communication is maintained throughout the entire process. 
Our side return extensions are designed to maximise the potential of underused areas beside your home. We begin with a site visit to understand your requirements and assess available options. From architectural drawings to construction, we oversee every stage. Typically, these projects add 15–25m² and take between 12 and 16 weeks to finish. 
Our loft conversion service offers a practical way to enhance your property without increasing its footprint. We begin with a site visit to understand your requirements and assess the roof structure. We then prepare drawings and obtain approvals where required. Construction is carefully coordinated from start to finish. 
Our approach to garage conversions combines careful planning with attentive project management. We examine the existing garage, including its connection to the main property and structural features. Once approvals are in place, we proceed with a fixed-price agreement. We remain in regular contact with you throughout the build. 
Through our full house renovation service, we modernise properties with a complete programme of works. This may involve extensions, loft conversions, and redesigned internal layouts. We also undertake kitchens, bathrooms, and finishing works as part of a single project. Every element is managed by our experienced design and build team.
Reviews (14)
Rebecca Cleaver
Jun 15, 2026
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We used Thames Design and Build for our single storey kitchen extension and wouldn't hesitate to recommend them. They helped us with the inital design and ideas through to architects plans and submission for planning permission. We then went on to use them for the build. From start to finish we found them to be professional, reliable, knowledgable and work to very high standards. Although we had a couple of unforseen challenges during the build - Thames Design & Build came up with solutions quickly and efficiently. Our project was spot on in terms of budget and timings. Communication at all times was excellent and the end result really did exceed our expectations. We would definitely use Thames Design & Build again in the future and would highly recommend them to anyone looking for a trustworthy, knowledgable design and construction company.
Sarah Moya
May 16, 2026
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Thames Design & Build recently completed a wraparound extension and full ground floor reconfiguration at our detached home in Surbiton. The project created a stunning open-plan kitchen, dining and living space, plus a new utility room and downstairs shower room. The team handled everything from the architectural drawings to the final build, making what could have been a stressful process remarkably smooth. Communication was excellent throughout - our project manager was always available and kept us updated at every stage. They delivered on time, stayed within the agreed budget, and the workmanship is first-class. The transformation has completely changed how we live in our home. Couldn't recommend them highly enough.
Mark Waterkeyn
May 07, 2026
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Danielle Domanski
Apr 15, 2026
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We have had very positive experiences working with Rob and his team to design and build our rear extension. The overall estimates were accurate and honored throughout, variations were discussed and agreed in advance and our project site lead, Ryan, was present and communicative throughout. The whole team respected our home and took care to leave it as they found it.
White & Lloyd
Apr 05, 2026
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B. Davis
Apr 02, 2026
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Rob and his team did an exceptional job converting my garage into a beautiful utility and w/c. Nothing was ever too much trouble. The team's attention to detail was amazing. The space was not easy to work with and they created bespoke solutions which fit our requirements beautifully with high quality craftsmanship. Highly recommend Thames Design & Build, and will be using again for future projects!
Tony Gold
Mar 09, 2026
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Rob Alison and his team built a single story extension to our home. I can recommend them as 100% reputable and reliable. The communication was excellent throughout the build, nothing was too much trouble for them.good people,a classy five star service of the first magnitude.
And a special thank you to Saema who coordinated the project from beginning to end!
And a special thank you to Saema who coordinated the project from beginning to end!
Sarah Townshend
Mar 17, 2025
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We contacted Thames Design & Build to help us with a bathroom renovation. Declan and his team carried out the fitting and we are delighted with the finished bathroom.
Everyone working on the renovation was friendly, professional and courteous and Declan was brilliant at communicating updates along the way.
Everyone working on the renovation was friendly, professional and courteous and Declan was brilliant at communicating updates along the way.
Paul Edwards
May 20, 2024
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Thames Design and Build did a full remodelling of our ground floor. We are delighted with the work Rob and his team have done. I would be happy to recommend them and would definitely use them again. The whole team were professional and friendly. Most importantly they are always contactable to discuss anything relating to the project (even out of hours) and gave good advice throughout.
Richard Jones
Apr 05, 2024
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Rob, Ryan and team provided an excellent service from start to finish. The design process was straightforward and build quotes reflecting changes to scope etc. were turned around very efficiently. Rob managed to get the build team started as soon as we took possession of the house and the build itself went extremely smoothly; the team were happy to accommodate changes as we went and everyone was extremely polite and professional. Of particular note was the speed of the build which meant that we were in the house only 5 months after the project started, this was far quicker than others were willing to commit to and reflects the strength of the company's supply chain, all of whom clearly enjoy working with Thames D&B and therefore are prepared to go the extra mile to get things done right first time. Special mention also for Saema who dealt doggedly with the aftercare to ensure that everything got sorted!
Lisa
Dec 27, 2023
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Robert Griessel
Jan 01, 2020
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Michael Wright
May 30, 2019
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Graham Wells
May 12, 2019
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Excellent company very proactive and professional approach to my requirements. Rear roof replaced and extension added. The team were so pleasant and a great find in james who ran the job. Tried to offer coffee and teas but they just wanted to "crack on! The boys were so tidy considering this is terraced house.