Renovation & Residential Extension Architects

At Gregory Phillips Architects, we believe that transforming an existing house can be just as exciting—and often more rewarding—than starting from scratch. Whether you’re extending, reconfiguring, or renovating, we create homes that reflect your lifestyle, aspirations, and the potential of the building itself. Our services are designed to guide you through the process seamlessly, from concept to completion, with creativity, clarity, and care.

Why Choose Gregory Phillips for Your Renovation and Extension?

We specialise in the thoughtful transformation of existing homes—breathing new life into properties through contemporary extensions, interior reconfigurations, and sensitive renovations. With over three decades of experience, our award-winning practice has delivered exceptional results across a range of contexts—from period properties in conservation areas to modern urban dwellings and countryside retreats.

Working with an existing structure comes with unique challenges—from site constraints to planning sensitivities—but also offers unique opportunities. Our team brings a depth of knowledge and creativity to every project, ensuring that the old and new are integrated beautifully, both functionally and architecturally.

Whether you’re looking to add space for a growing family, improve natural light and flow, or reimagine your home for modern living, we have the expertise to deliver a result that feels entirely new—while respecting what already exists.

Our Process for Renovation and Extensions

Our process is specifically tailored to the complexities of working with existing buildings. We begin by understanding your objectives—whether spatial, aesthetic, or functional—and analysing the potential of your property. We consider site constraints, planning policies, and the architectural language of your home.

From there, we develop a concept that transforms your space—enhancing light, flow, proportion, and connection to the outdoors. We produce 3D visualisations, feasibility studies, and cost estimates early in the process to provide confidence and clarity.

We handle all aspects of the planning and statutory approvals process, including listed building consent where required. We coordinate necessary surveys and engage with trusted consultants to ensure a smooth path to approval.

Our technical detailed design phase prepares your project for construction, with detailed drawings and specifications. Whether you’re extending outwards, upwards, or reconfiguring internally, we design every element to a high level of precision and intent.

Throughout construction, we remain closely involved—monitoring quality, advising on finishes, and ensuring the design is faithfully delivered. We oversee the final stages, guide you through the handover, and provide ongoing support post-completion.

You can find out more about our seven-stage process here.

Sustainable and Thoughtful Design

As we move into a future of more responsible construction, our renovation and extension projects are designed with sustainability at their core. Reusing and upgrading existing structures is one of the most sustainable ways to improve a home—and we enhance this further through energy-efficient technologies, low-carbon materials, and high-performance detailing.

From upgraded insulation and glazing to the integration of renewable energy systems and smart home technologies, we ensure your transformed home is not only beautiful, but future ready. Our approach balances environmental performance with comfort, style, and longevity.

Transform Your Existing Home with Confidence

Whether you’re looking to modernise a period home, add space through a bold extension, or completely reimagine the way your home works for you, Gregory Phillips Architects can help you unlock its full potential.

Contact us to arrange a consultation and take the first step towards transforming your home.

Residential extension architects

A well-thought-out and executed extension adds so much to a home. Not only does it increase the amount of available space, but it should add substantially to the monetary value of the property. Planning an extension is an opportunity to examine the needs of the household, and ways of enhancing the usability of the existing space while increasing the square footage. What will the extension be used for? Does it make sense to move existing uses into the new space and repurpose some of the other rooms?

Award-winning design

We have an excellent track record of designing award-winning, beautifully crafted, extensions that flow seamlessly from the existing property, adding more room and enhancing the lifestyle of the homeowners. By engaging in a collaborative process, we maximise the potential of our clients’ existing properties to deliver extensions of exceptional architectural quality. Through our attention to detail, proportion and scale, we design sculptural forms which complement and respect the character of the existing building while adding extra space and natural daylight. Our consultative process helps clients to see the scope for remodelling or repurposing their current home in conjunction with the extension to maximize its potential and their enjoyment.

Creating unique designs

We have experience designing extensions for a wide variety of existing homes from contemporary buildings to Victorian houses to Grade II listed properties, working within relevant planning constraints and opportunities. We are well known for our fusion of traditional and contemporary design when we work with older buildings. We have worked with properties of all sizes, in urban or rural settings.

Our designs can incorporate not just the structure but a complete interior design service, and a landscaping design to complement the new addition to the building. This allows a harmonious flow from inside to out, and from new build extension to existing structure. We work collaboratively with landscape designers to reflect the vision of the architecture.

We have completed many extension projects in London, including an extension in Muswell Hill that won the Daily Telegraph Home Renovation Award for Best Extension / Remodeling, as well as being acclaimed in the Grand Design awards for the extension design.

Other extension projects in London include a historic terraced house in Kensington with a contemporary extension that also included a complete remodelling of the rest of the property. In Chiswick, we carried out work to a grand Victorian house where an innovative modern extension including glass facades and external reflecting pool was added. The extension to a traditional Arts and Crafts detached 600 sqm house incorporates a contemporary garden design creating unique indoor-outdoor living spaces.

Going beyond the city

We do not only operate inside London. We provide top quality design services to property owners throughout the UK and beyond. For a Grade II listed farmhouse in Kent we designed and managed a project including extensive refurbishment, reconfiguration and an extension that not only added substantially to the family living space but brought more light into the property through the contemporary design.

In Guildford we took on the work of renovating an existing Grade II Listed detached house set within 30 acres. This included the addition of a new 100 sqm two-story wing providing a family room/kitchen on the upper floor and an indoor swimming pool at lower ground level.

About Gregory Phillips architects

We provide a unique, considered and professional approach to high quality residential design.

We have produced many award-winning projects for both architecture and interior design; our most recent works include new build contemporary homes, basement excavation, substantial residential extensions, new swimming pools and remodelling projects.