James Williamson Architects Ltd is a Surrey-based RIBA Chartered architectural practice providing high-quality residential architecture for private homeowners. We specialise in delivering clear, well-structured professional support, combining regulatory expertise with carefully considered design solutions. Our approach is focused on reducing complexity and ensuring clients are well informed at every stage.Our practice concentrates on residential extensions, renovations, retrofits, and bespoke new-build houses throughout Surrey and the wider South East. We undertake projects ranging from loft conversions and kitchen reconfigurations to whole-house renovations, low-energy retrofits, heritage properties, and custom-designed new homes. Clients are supported from early feasibility and planning strategy through to detailed design, approvals, and construction-stage involvement. We emphasise buildability, technical clarity, and risk management, including our responsibilities as Principal Designer under the CDM Regulations. Sustainability is embedded within our work through fabric-first principles, energy-efficient layouts, and sensitive interventions to existing buildings. With strong local planning knowledge and a client-focused ethos, we help homeowners achieve practical, comfortable, and durable homes.
Served areas
- Surrey, Sussex, Berkshire, Hampshire, London
Business details
- Year established: 2020
- Employees: 4
- Licensed
- Insured
Highlights and features
- RIBA Chartered architect delivering clarity, confidence, and calm.
- Bespoke renovations, extensions, and new-build homes designed.
- Planning advice and feasibility studies to unlock potential.
- Passive House and EnerPHit retrofits for efficient living.
- Collaborative 3D and virtual reality design visualisation.
- End-to-end support, from permissions through to completion.
Associations and certifications
- RIBA Chartered Practice
Payment methods
- Debit cards, Credit cards, Mobile payments, Bank transfers
Services
We help clients unlock the full potential of their homes without the upheaval of moving. By offering a clear, step-by-step process, we replace uncertainty with informed choices. Each project is designed to improve flow, comfort and practicality, resulting in homes that feel calmer, brighter and better suited to family living. 
Our new build process is designed to replace uncertainty with clarity and control. We begin by understanding our clients priorities before shaping a design that balances beauty, practicality, and efficiency. Throughout the project, we manage consultants, approvals, and technical detail. This structured approach supports smooth delivery and reliable outcomes. 
We support the restoration and adaptation of historic homes through careful conservation-led design. Our role is to balance regulatory requirements with our clients aspirations, ensuring each intervention is appropriate and enduring. With clear advice and considered solutions, we help create homes that honour the past and serve the future. 
Our interior architecture service transforms uncertainty into informed decision-making. We carefully plan each stage, ensuring that design intent, budget awareness, and practical delivery remain aligned. Through thoughtful detailing and sustainable principles, we create interiors that feel intuitive to use, visually refined, and capable of supporting everyday living.
People
James Williamson
RIBA Chartered Architect
I am James Williamson, a RIBA Chartered Architect. Raised in the South West, I value architecture that responds discreetly to its setting and improves everyday living. Following more than a decade with award-winning practices in the UK and overseas, I established James Williamson Architects in 2020. My aim is to help clients create homes that feel intuitive, lasting and personal.
Reviews (7)
John Armenakas
Sep 19, 2025
James was wonderful to work with, and provided us with 2 wonderful designs that captured everything we wanted in our extension. Once we decided the design we wanted to move forward with, James worked through the planning approval process for us. The results are amazing, and we are so happy with the way our extension looks.
Tom Wood
Dec 30, 2024
Heather Steen
Nov 28, 2024
Our experience with James was fantastic throughout!
After an initial survey of the space, and design proposal, we had in-depth discussions with James together with our builder. He listened to our thoughts and preferences, took time to answer questions really clearly and show us options, before we agreed on a final plan. We were really pleased to have James back to visit to see the end result.
I would thoroughly recommend!
After an initial survey of the space, and design proposal, we had in-depth discussions with James together with our builder. He listened to our thoughts and preferences, took time to answer questions really clearly and show us options, before we agreed on a final plan. We were really pleased to have James back to visit to see the end result.
I would thoroughly recommend!
Daniella Taggart
Aug 22, 2024
Sally Hewison
Sep 15, 2023
We engaged James to explore the possibility of updating our small bungalow and incorporating an additional bedroom and bathroom. Communication was very smooth and James listened attentively, understood the brief well and produced an imaginative design which used the limited space available to its best advantage. The design included floor plans and a 3D virtual walkthrough. We decided for personal reasons not to go further at the present time, but if our situation changes in the future we will be more than happy to continue working with JWA
Graham Walpole
Aug 07, 2023
Joseph Kane
Jun 23, 2023
James designed a wrap around extension to our Victorian terraced house and we couldnt be happier with the job he did. Very straightforward to deal with, fantastic design proposals and great imagery to help us visualise the different options. The technical drawings he prepared were very accurate which helped make the build process as straightforward as it could be. Would definitely recommend.