Upgrade Without Starting Again
Our retrofit service applies Passivhaus principles to existing buildings, improving comfort, efficiency and long-term resilience.
Through a carefully planned, fabric-first approach, we address the underlying causes of heat loss, drafts and inefficiency to create homes that perform consistently all year round.
Comfort Focused
We prioritise insulation, airtightness and ventilation to create stable, comfortable indoor environments.
Proven Standards
Using the EnerPHit framework ensures upgrades are structured, measurable and genuinely effective.
Long-Term Impact
Every improvement is designed to deliver lasting benefits, reducing running costs and extending the life of your home.
From the Founder
“Retrofitting is one of the most powerful ways to improve how a home performs and feels. When it’s done properly, the difference is immediate and lasting.”
Joshua Day
Founder & Director
“From our first conversation to the final handover, the whole experience felt calm and well managed. Everything was clearly explained and we always felt informed. The house is incredibly comfortable and performs better than we imagined. We wouldn’t hesitate to recommend Myzsa.”
Sarah Collins
New Build Construction
“We were nervous about extending our home, but Myzsa guided us through every step with clarity and care. The workmanship is exceptional and the finished space feels seamless, warm and thoughtfully designed. It’s completely transformed how we live in our home.”
James Thornton
Conversion & Extension
“The retrofit has made a huge difference to our day-to-day comfort. The house is warmer, quieter and far more efficient. The team explained the process clearly and delivered exactly what they promised. It’s one of the best decisions we’ve made.”
Emma Richardson
Retrofit (EnerPHit)
“From start to finish, the process was professional and transparent. The attention to detail and focus on performance really stood out. Our home now feels solid, comfortable and future-proofed. We felt confident in their expertise throughout.”
Mark Evans
Building Fabric & Renewables Upgrades
“Achieving Passivhaus certification felt daunting at first, but Myzsa made the process clear and manageable. Their quality control and testing gave us total confidence, and the final result speaks for itself. The performance of the building is outstanding.”
Laura Bennett
Passivhaus Certification & Quality Control
“What impressed us most was how listened to we felt. Every decision was explained, and the result is a home that feels calm, efficient and beautifully built. The experience was smooth from beginning to end, and the quality is evident in every detail.”
David Walker
New Build Construction
Transform the Home You’re In
If you’re ready to improve comfort, efficiency and performance without rebuilding, we’ll help you plan a retrofit that delivers real, measurable change.
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