How to find the right retrofit architect in London
Retrofit requires a genuinely different set of skills from new build. That sounds like a simple statement, but its implications run deep: how a practice surveys an existing building, how it thinks about materials, how it understands construction history, how it manages the relationship between old and new fabric, and how it responds to a very different set of site conditions.
Finding a retrofit architect who is genuinely an expert, rather than just willing to take on retrofit work, is worth the effort. Here’s what to look for.
The skills a retrofit specialist brings
A retrofit architect needs to understand how buildings behave, not just how they were designed to behave. That means understanding heat loss through solid walls, moisture movement in traditional construction, the thermal bridging risks in typical retrofit details, and the interaction between improved airtightness and ventilation.
It also means being material-literate. Retrofit in older London buildings often involves reclaimed materials, lime-based products, natural insulation, and careful detailing at the junctions between old and new. A practice that has worked extensively with these materials will make faster, better decisions than one encountering them for the first time on your project.
And it means having a design sensibility that is activated, not constrained, by existing buildings. The best retrofit architects find genuine creativity in what’s already there.
Credentials to look for
RIBA Chartered Practice: the baseline for professional standards, insurance, and accountability.
Completed retrofit projects, not just new build experience: ask specifically for examples of retrofit work at a similar scale and building type to yours.
Experience with the specific building type: a practice that specialises in Victorian residential retrofit may not have relevant expertise for a post-war school, and vice versa.
Knowledge of whole life carbon: not all practices have caught up with embodied carbon assessment. Those that have will make better decisions for you.
Passivhaus certification (where relevant): particularly useful for deep residential retrofit where achieving very high energy performance is a goal. Not essential for all retrofit projects.
Questions to ask
Can you show me a completed retrofit project and walk me through the key decisions you made about the existing fabric?
How do you approach the survey and investigation phase — what are you looking for and how does that inform the design?
How do you handle the relationship between improved airtightness and ventilation in an older building?
What’s your experience with reclaimed and natural materials, and do you have established supplier relationships?
How do you think about the character of the existing building — what’s worth preserving and what can be changed?
Listen for specific answers, not generalities. The practice that can tell you exactly how they approached a particular junction detail, or explain why they chose a specific insulation product for a specific situation, is the one that knows what it’s doing.
Assessing a portfolio for genuine retrofit expertise
Look at the portfolio carefully. Retrofit work should show buildings that are clearly old, with new interventions that are intelligent about what they’re working with. Look for evidence of material thinking — not just visual outcomes but decisions about what was kept, what was stripped away, and why.
Be wary of portfolios that are dominated by new build work with one or two retrofit projects included. Retrofit is a specialism; it rewards practices that have made it a sustained focus.
Values alignment
This matters more than it might seem. Retrofit is inherently a values-driven approach to architecture. It starts from a position of respect for what already exists, and a commitment to working with it rather than against it. A practice that shares those values will make better decisions throughout the project, particularly when the inevitable complications arise.
The best retrofit projects we’ve been involved with have been genuine collaborations — between us, our clients, and the buildings themselves. That requires a shared understanding of what we’re trying to achieve and why it matters.
Retrofit architecture in London: everything you need to know
What does a retrofit project actually cost in London?
Talk to us about your retrofit project
