Architectural & Building Services
Thames Design & Build is proud to provide residential design and build services throughout South West London and Surrey. Since our founding by Rob Allison in 2011, we have assembled a team of designers, project managers and skilled tradespeople who understand how to balance design intent with the realities of construction. We work across areas including Esher, Richmond, Kingston, Leatherhead, Dorking and Twickenham, assisting homeowners who wish to extend, convert or reconfigure their properties. Whether a project begins with existing drawings or a blank sheet of paper, we are committed to helping our clients progress with clarity and confidence.
By delivering both architectural and construction services, we provide a streamlined experience from concept through to completion. Our work includes rear extensions, loft conversions, garage conversions, side return extensions, two-storey extensions and complete house renovations. We also manage planning applications, approvals and project delivery, ensuring each phase receives the attention it deserves. With qualified professionals across every discipline, including Gas Safe registered plumbers and ECA registered electricians, we bring local knowledge and practical expertise to every home improvement project entrusted to us.
Served areas
- Kingston Upon Thames, Thames Ditton, Esher, Molesey, Walton-on-Thames, Weybridge, Cobham, Oxshott, Wimbledon, Richmond, Epsom, Leatherhead, Twickenham, Sheen, Kew, Dorking, Guildford
Business 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
We bring together design expertise and construction knowledge to deliver outstanding residential projects. Our specialisms include home extensions, loft conversions, renovations, and bespoke architectural services. Each project is approached with a focus on quality and practicality. From initial planning to final construction, we work to achieve spaces that meet our clients' expectations. 
We provide expertly managed rear extensions from the earliest planning stages to the final handover. Our team develops architectural drawings and arranges approvals where required. Throughout the build, a dedicated site manager coordinates all trades. The finished extension is designed to feel like a natural part of your home. 
We provide professionally managed kitchen extensions designed to transform the centre of your home. Every project begins with a consultation and site visit to establish what can be achieved. Our specialists then prepare designs and oversee approvals. From structural work to finishing touches, we manage the complete build on your behalf. 
We create side return extensions that turn unused side passages into valuable ground floor living space. This solution is especially suited to Victorian and Edwardian terraced and semi-detached homes. Our team manages the entire process from design to completion. Most projects provide 15–25m² of additional space and are completed within 12–16 weeks. 
Through our loft conversion service, we create additional living space without extending beyond your property's existing footprint. We oversee the project from the first site visit through to final completion. Every element of the construction is carefully managed by our team. Clients receive regular updates throughout the build. 
Adding usable living space through a garage conversion can be a highly cost-effective home improvement. We carry out an initial survey to identify important construction considerations. Our team then prepares designs and manages approvals where necessary. During construction, we keep you informed at every stage of the project. 
Our full house renovations bring together structural works and interior enhancements within a single service. We oversee extensions, loft conversions, and internal alterations alongside kitchens and bathrooms. Each project follows a structured process beginning with design and ending with completion. By managing all trades directly, we help keep projects running smoothly.
Reviews (14)
A. C.
Jun 23, 2026
We engaged Thames Design & Build for our internal alterations and refurbishment project at our home in Surbiton. We chose them because we wanted a company that took care of both the design process and the build. Kris managed our project and kept us informed throughout with weekly on-site meetings, and the work was completed on time and on budget. The project has transformed our ground floor from a poorly laid-out, dark space into a light, airy one that suits our lives so much better. We wouldn't hesitate to recommend Thames Design & Build to anyone looking to carry out similar layout alterations and refurbishment work in the Surbiton area.
Sarah Moya
May 16, 2026
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
B. Davis
Apr 02, 2026
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!
Susan
Jul 16, 2025
Stephanie Taylor
May 02, 2025
Emma Murphy
Dec 14, 2024
Richard Jones
Apr 05, 2024
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!
T. Fraser
Apr 02, 2024
When we needed to extend our ground floor, redesign the layout of the property, and do a hip-to-gable roof conversion we chose Rob and the team at Thames Design and Build. From the initial architect drawings, to the planning process, costings, project and supplier and specialist management, we were provided with excellent support. Ongoing communications and guidance throughout the project ensured that for our first build we were able to reduce the stress and uncertainty that comes along with such a big life decision. The project was finished on time and to a great spec. We would highly recommend Rob and the team for any home project - big or small.
Jenny Hogg
Jan 22, 2024
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
Jane Bone
Jul 21, 2019
Eliza Sophia
Apr 20, 2019
Cady Allen
Apr 07, 2019
Thames Design & Build worked with us on our house renovation to produce the Design Drawings (with layout options) and Technical Drawings for planning and surveyor. Not only were the team incredibly knowledgeable and professional, they were an absolute pleasure to work with and went above and beyond to support us through what was a daunting and potentially stressful experience. Having such a credible team on board with us immediately put as at ease, meaning we could enjoy our exciting project - we knew we were in safe hands with them and they delivered! A huge thank you to Rob and his team!