We established Thames Design & Build to provide homeowners with a straightforward and dependable route to improving their properties. Since Rob Allison founded the company in 2011, we have worked extensively across South West London and Surrey, supporting clients in Kingston, Thames Ditton, Wimbledon, Richmond, Esher and surrounding areas. Our expertise lies in residential extensions, loft conversions and structural works, supported by a team that understands both architectural principles and the demands of construction. Regardless of where our clients are in their journey, we help them move forward with practical advice and experienced guidance.
Our services extend from the preparation of architectural plans and planning applications through to construction, project management and completion. Keeping design and building services within one organisation allows us to maintain continuity throughout every stage of delivery. Our qualified team includes project managers, designers and trusted tradespeople, alongside Gas Safe registered plumbers and ECA registered electricians. We undertake rear and side return extensions, kitchen and wraparound extensions, garage conversions, two-storey additions and comprehensive house renovations, always with the aim of delivering homes that are both functional and thoughtfully designed.
Our services extend from the preparation of architectural plans and planning applications through to construction, project management and completion. Keeping design and building services within one organisation allows us to maintain continuity throughout every stage of delivery. Our qualified team includes project managers, designers and trusted tradespeople, alongside Gas Safe registered plumbers and ECA registered electricians. We undertake rear and side return extensions, kitchen and wraparound extensions, garage conversions, two-storey additions and comprehensive house renovations, always with the aim of delivering homes that are both functional and thoughtfully designed.
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
Our team provides an integrated approach to residential design and construction. We undertake home extensions, loft conversions, renovations, and bespoke architectural work with equal dedication. Quality remains central to everything we do. Through coordinated planning, design, and building services, we assist homeowners in bringing their ideal living spaces to life. 
With our rear extension service, we help transform underused space into practical and inviting living areas. We take care of design, planning applications, and building regulations where applicable. Construction is managed in full by our experienced team. We ensure every detail is completed to a high standard from start to finish. 
We offer a complete kitchen extension service, managing projects from concept through to handover. After an initial site visit, we develop architectural drawings and arrange the required approvals. A fixed-price quote is issued before construction begins. Every stage is coordinated by our experienced team to ensure a seamless delivery. 
We provide complete side return extension solutions for homeowners seeking additional ground floor space. The process starts with a detailed site assessment before moving into design and approvals. Our experienced team handles structural work, plumbing, electrics, glazing, and finishes. In most cases, the completed extension adds between 15 and 25 square metres. 
We deliver loft conversions that create valuable additional space within your home. Whether you require a bedroom, home office, or another living area, we manage every stage of the project. From design to completion, our team oversees the process with care. Most work remains within the roof space, helping to minimise disruption. 
We transform underused garages into practical living spaces tailored to your household's needs. Our team manages the entire process, from the initial survey and design drawings to completion. We assess key structural elements at the outset. Throughout the build, we provide clear updates and dedicated project management. 
We specialise in delivering complete house renovations with careful attention to planning and execution. Every project starts with an in-depth consultation to establish your requirements. Our team manages approvals, coordinates construction activities, and supervises finishing works throughout. With one team responsible for the entire process, consistency is maintained from start to finish.
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.
Andrew Ashbourne
Jun 04, 2026
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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.
Ksp Carpentry & Building Solutions Ltd
May 16, 2026
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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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Jane McKeown
Dec 23, 2025
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TD&B designed and built a wrap around single storey kitchen extension, installed a toilet and new bathroom and took out a chimney. We are really pleased with the work and all of the guys that worked on the job, who were friendly and professional throughout and mindful of our neighbours. The different specialists worked seamlessly together from our perspective. Our foreman Marlon in particular was exceptional in pulling the whole thing together and he is brilliantly solution- and customer- focussed. We are very glad we picked TD&B . The contract and quote were very professional and transparent and the only variations were ones we expected or resulted from choices we made. All of the pricing, including variations, was very clear and the accounting speedy. Communication was great throughout. All finished on time too.
Jenny Hogg
Jan 22, 2024
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We can honestly say that Thames Design & Build offer and give a great service. They were quick to respond with clear and concise quote. Their team arrived on time and kept us up to date with a schedule, timings and variations. Everything is handled by a project manager but all members of the team were polite and more than happy to explain anything. We commissioned them for a rebuild project. Quality of workmanship has been great and any problems quickly resolved. Great customer service, communication and workmanship. Wouldn’t hesitate to recommend.
Lisa
Dec 27, 2023
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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.
Eliza Sophia
Apr 20, 2019
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Mel Branson
Mar 12, 2019
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Rob Allinson and the project team provided an extremely professional service from the drawing board through to completion of the works. The brief was set to provide a design and build solution for our loft that was in-keeping with the Edwardian house, and Thames Design & Build Ltd delivered the project to our exacting requirements. They managed the relationship and process with building control and were very proficient in transitioning design work into a high quality build. The work was completed on programme and to budget. We would have no hesitation in recommending Rob and the team.