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by Sean Hill on Jul 30, 2025
Every build is a decision. Every decision shapes the future.
When we begin a new project—whether it’s a quiet retrofit of a London terrace or a bold new home emerging from a rural hillside—we start with a simple question: what kind of future are we building for?
Choosing the right standard for energy and performance is not just about ticking regulatory boxes. It’s about making choices that align with your values, your budget, and the long-term performance of your home or building. Below, we unpack the standards that are shaping sustainable architecture today—and how we apply them in our work at RISE.
A low-energy rear extension and retrofit of a London home, blending natural materials with high-performance detailing to meet EnerPHit principles.
The Baseline: Building Regulations (Part L)
Let’s start at the bottom line. UK Building Regulations, particularly Part L (Conservation of Fuel & Power), define the minimum legal standard. But minimum isn’t where meaningful design begins.
Yes, Part L ensures basic compliance with insulation, energy efficiency, and carbon emissions. But for those who care about comfort, cost-in-use, and climate impact, this is just the starting point.
At RISE, we design to go well beyond Part L. We believe it’s what you don’t see on your energy bill—or feel in a draught—that defines real success.
Part L of the UK Building Regulations sets the legal minimum for energy efficiency—but at RISE, we see it as just the starting point for sustainable architecture.
Passivhaus: Design for Performance, Not Just Appearance
☉ Imagine living in a space that barely needs heating.
☉ A space where filtered fresh air flows through every room.
☉ A space that performs just as brilliantly as it was designed to.
That’s Passivhaus.
This rigorous German standard has become the benchmark for ultra-low energy buildings. It doesn’t rely on gimmicks or greenwashing. It’s all about getting the fundamentals right—airtightness, insulation, orientation, solar gain, ventilation.
And it’s not just theory. Passivhaus certification includes checks at every step—design modelling, construction detailing, onsite testing—so what gets built actually delivers. In our view, that level of accountability is rare, and increasingly vital in a world of climate targets and rising fuel costs.
We’ve applied these principles on retrofit and new-build projects across London. The result? Warm, healthy, future-proof homes with heating bills that barely make a mark.
Passivhaus Certification sets a benchmark for thermal comfort, airtightness and energy use, ensuring your building performs exactly as it was designed to.
EnerPHit: Passivhaus for Retrofits
Upgrading an existing home? That’s where EnerPHit comes in.
Developed by the Passivhaus Institut, EnerPHit adapts Passivhaus thinking to the constraints of older buildings. It accepts that you might not get perfection—but it still pushes hard toward performance. Lower energy demand. Cleaner indoor air. Materials and methods that make your home resilient, not just refreshed.
We see EnerPHit as the gold standard for retrofit. It’s ambitious, but not unattainable—and the results speak for themselves in comfort and carbon.
EnerPHit is the Passivhaus standard for retrofit projects, designed to elevate existing buildings to exceptional levels of energy performance and comfort.
AECB: Simpler, Smarter Sustainability
For projects where full Passivhaus certification isn’t quite right, the AECB standard offers a pragmatic step up from Building Regs.
Built on the same modelling engine (PHPP) as Passivhaus, the AECB standard enables you to design a high-performance building with more flexibility and less bureaucracy. It's performance-based, not points-based. That’s why we like it—it focuses on outcomes, not optics.
The best part? It’s grounded in real-world construction costs. For many clients, especially those in smaller homes or tighter sites, it strikes the right balance between ambition and affordability.
The AECB CarbonLite standards offer a pragmatic approach to low-energy design, with separate pathways for new builds and retrofits grounded in real-world performance.
Beyond Energy: Health, Ecology + Human-Centred Design
Not every standard is about kilowatt hours.
Some are about how a building feels—its atmosphere, its materials, its effect on our health and wellbeing. That’s where Building Biology comes in.
Developed in Germany, Building Biology focuses on indoor pollutants, electromagnetic fields, moisture, light levels and biological rhythms. It invites us to think about architecture not just as shelter, but as habitat.
We see this as part of a deeper movement—one where architecture responds not only to the climate crisis, but to the need for buildings that nurture human beings. It’s why we favour natural finishes, breathable construction, and VOC-free materials wherever possible.
BREEAM: Sustainability at Scale
For larger developments and commercial schemes, BREEAM has become the standard bearer for environmental performance.
It evaluates sustainability across a wide range of categories—from water use and waste to biodiversity and adaptability to climate change. What it lacks in simplicity, it makes up for in breadth. It encourages cross-discipline collaboration from the earliest design stages to post-occupancy.
We often work alongside BREEAM assessors on our larger or institutional projects. When used well, it keeps everyone—clients, consultants, and contractors—accountable to more than just deadlines. It helps ensure that sustainable thinking runs all the way through the project, not just around the edges.
BREEAM takes a broad-spectrum view of sustainability—assessing buildings across categories like energy, transport, materials, ecology and wellbeing to ensure long-term environmental resilience.
Certification or Not?
It’s worth asking: is it essential to certify?
Not always. A building designed to Passivhaus standards but not officially certified can still perform well—if the right processes are followed and tested along the way. But certification adds a layer of independent scrutiny that protects both the design intent and the client’s investment.
For us, certification is less about the plaque on the wall and more about the performance in the winter. It’s a tool for quality assurance, not a badge for marketing.
What’s the Best Standard for You?
There’s no one-size-fits-all answer. The best standard is the one that aligns with:
← Your values
← Your budget
← Your site constraints
← And your vision of how you want to live or work
We’re here to guide you through those choices. We’ll explain the trade-offs, test the design options, and help you find the sweet spot between sustainability and buildability.
Building for the future
At RISE, we believe that choosing the right building standard isn’t just a technical decision. It’s a declaration of intent – to tread lightly, to build wisely, and to create spaces that stand the test of time.
Whether it’s Passivhaus precision, AECB pragmatism, or EnerPHit ambition, each path is a step toward something greater – homes and buildings that respect their context, care for their occupants, and give back to the environment.
Thinking about how to future-proof your project?
Let’s explore how your building can rise with purpose – and perform for generations to come.
→ Email us at architects@risedesignstudio.co.uk
→ Or call the studio on 020 3947 5886
RISE Design Studio Architects, Interior Designers + Sustainability Experts
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