Old Bones, New Life: How One Mews House is Leading a Low-Carbon Future

In the heart of W2, nestled behind the grand stuccoed avenues of Bayswater, sits one of London’s best-kept secrets: Bathurst Mews. A cobbled street once home to horses and hay carts, it's now a serene pocket of heritage homes where ivy climbs brick walls and life hums quietly behind pastel-painted doors. But behind this picture-postcard façade, these old houses are telling a quieter story - one of energy loss, discomfort, and environmental cost.

This is the story of how one humble mews house is being transformed into a beacon of the future.

At RISE Design Studio, we see buildings as living organisms - capable of growth, transformation, and longevity, if only we give them the care and vision they deserve. Our project on Bathurst Mews in Bayswater is one such transformation. We’re retrofitting a mid-terrace home to EnerPHit standards - bringing 19th-century bones into the 21st century, and leading the way toward a low-carbon future for heritage housing.

☉ What Makes Bathurst Mews So Special?

To understand the significance of this project, you have to understand the fabric of the street itself. Bathurst Mews isn’t just another quaint corner of London - it’s part of the city’s architectural soul. Originally built to house stable hands and carriages, mews homes were humble, utilitarian, and often overlooked. Today, they’ve become sought-after residences full of character and charm.

But beneath their charm lies a problem common to many of London’s historic homes: they leak energy like sieves. No insulation. Single glazing. Cold bridges in every corner. Air that escapes as fast as the heat it carries. In winter, it’s not uncommon to wear jumpers indoors. In summer, these homes become stifling. For those who live in them, it’s more than uncomfortable - it’s unsustainable.

☉ Enter EnerPHit: Deep Retrofit for a New Era

Our response at RISE was not to tear down and rebuild, but to reimagine what this building could be - and do it with empathy for its past.

EnerPHit is the retrofit equivalent of the rigorous Passivhaus standard. Where Passivhaus is the benchmark for new-build low-energy homes, EnerPHit sets the gold standard for transforming existing buildings. And it’s not for the faint-hearted.

To meet this standard, we had to:

• Wrap the entire building envelope in super insulation

• Fit triple-glazed timber windows throughout

• Seal every join to create a completely airtight layer

• Install a Mechanical Ventilation with Heat Recovery (MVHR) system to deliver fresh, filtered air with minimal heat loss

• Integrate solar panels and select materials with low embodied carbon

• Use breathable natural insulation where needed to allow the historic structure to perform as it was originally designed

In short, this isn’t just a facelift - it’s a full systems upgrade. The result? An 80–85% reduction in energy use, year-round comfort, and pristine indoor air quality. And all this without losing the soul of the original home.

☉ Designing for Heritage and Performance

You might ask: how do you do all that without destroying the character of a heritage street?

That’s the magic - and the challenge - of good retrofit design. Preservation doesn’t mean stasis. It means knowing what to hold onto and what to evolve. The front of the house on Bathurst Mews retains its original brickwork, sash-style windows (now triple-glazed), and the human scale that makes this street so beloved. Behind the scenes, the story is radically different.

The insulation is hidden within layers of carefully detailed construction. Services are run with surgical precision. Ventilation outlets are discreet. Even the solar panels are placed to minimise visual impact. This is architecture as quiet performance - honest, elegant, and deeply effective.

☉ Why It Matters: The Carbon Cost of Doing Nothing

We’re often told that “the greenest building is the one that already exists.” But unless we intervene, existing homes will continue to underperform. In the UK, the built environment accounts for nearly 40% of total carbon emissions, and much of that comes from domestic heating and cooling.

London has a uniquely rich stock of historic homes, but also a uniquely leaky one. Without action, these buildings will become uninhabitable in a future of rising energy costs and climate extremes.

Retrofitting isn’t just an architectural upgrade - it’s an environmental necessity. It’s how we bridge the gap between past and future. And it’s how we make our homes not just beautiful, but sustainable, healthy, and resilient.

☉ What You Can Learn from This Retrofit

Many homes across the UK - whether mews, mansion block, or Victorian terrace - share a similar construction age. Timber joists, solid brick walls, and lath and plaster ceilings. These are buildings of great charm and dignity. But they weren’t designed for today’s climate, nor for the way we live now.

What if your home could feel warm on the coldest day of the year, using just a fraction of the energy it does today?
What if you could dramatically reduce your bills, improve your indoor air quality, and lower your carbon footprint - without changing the character of your home?

That’s the promise of high-quality retrofit. And it’s not out of reach.

☉ Lessons from Bathurst Mews: A Retrofit Blueprint

Here are six insights from our work on Bathurst Mews:

1. Start with a fabric-first approach
   Before adding solar panels or fancy gadgets, tackle the basics. Insulation, airtightness, and quality windows will always give the biggest return.

2. Plan holistically, not piecemeal
   Retrofits work best when considered as a complete system. Every element interacts. Seal up one part and ignore another, and you may create condensation or cold bridges.

3. Ventilation is non-negotiable
   Once a building is airtight, it needs smart ventilation. MVHR systems ensure healthy air without throwing away heat.

4. Use natural, breathable materials
   Especially in older homes, breathable construction helps regulate moisture and reduces the risk of mould or fabric decay.

5. Engage early with planning authorities
   Even if your building isn’t listed, its location may fall within a conservation area. Start conversations early and bring clear, well-considered proposals.

6. Choose a team with retrofit experience
   Retrofitting is not like new build. It demands a forensic understanding of existing fabric, thermal bridging, and sequencing. Make sure your architect and contractor know the territory.

☉ Why Retrofit Isn’t Just for Grand Designs

We’ve worked on mews homes, terraced houses, schools, restaurants, and cultural buildings. The challenges are different in each case, but the principle is the same: work with what exists, and help it evolve.

You don’t need a mansion or a huge budget to benefit from EnerPHit principles. Even small improvements - like internal wall insulation or better glazing - can have a huge impact. And over time, as more people embrace this approach, the cumulative effect will be profound.

☉ From Embodied Carbon to Emotional Value

There’s another reason we retrofit: emotional value.

These buildings have stories. Layers of lives. They’ve stood through wars, witnessed change, survived neglect, and now face their greatest challenge - climate collapse.

When we retrofit, we’re not just saving energy. We’re honouring the past and investing in the future. We’re creating spaces that feel good to live in - calm, consistent, breathable, secure. And we’re doing it with care, not compromise.

☉ The RISE Way: Architecture with a Conscience

At RISE Design Studio, we approach each project as a conversation with the building, with its environment, and with the people who inhabit it. We don’t believe in off-the-shelf solutions. We believe in crafting.

Whether we’re designing a low-energy cinema, adapting a Victorian terrace, or building a timber-framed home in the countryside, we lead with sustainability, beauty, and purpose. Our work is driven by one core idea: design should make life better - for people, and for the planet.

We’re proud that Bathurst Mews is setting the tone for what heritage homes can be. Not just relics of the past, but pioneers of the future.

If you would like to talk through your project with the team, please do get in touch at architects@risedesignstudio.co.uk or give us a call on 020 3947 5886

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