Metro Central Heights
Deep Retrofit of a Grade II Listed Apartment
Set within Metro Central Heights in London, this project explores how a mid-century modernist apartment can be carefully re-engineered to meet contemporary environmental standards - without compromising its architectural heritage.
Occupying the third floor, the 56 sqm flat comprises two bedrooms (one en-suite), a separate bathroom, and an open-plan living, kitchen and dining space. While compact, the original layout lacked environmental coherence: inconsistent temperatures, poor air quality, and significant heat loss limited both comfort and efficiency. Our approach was to treat the apartment as a complete environmental system - where spatial design, building fabric, and services operate as one.
Working within a Grade II listed context, we adopted a rigorous, fabric-first methodology informed by Passivhaus principles. This required a precise calibration of insulation, airtightness, and junction detailing. Thermal bridges, common in buildings of this era, were carefully analysed and mitigated, while airtightness strategies were integrated discreetly within the existing structure to reduce uncontrolled air leakage.
At the core of the retrofit is a Mechanical Ventilation with Heat Recovery (MVHR) system. This ensures a continuous, balanced supply of fresh air while recovering heat from extracted air, dramatically improving indoor air quality and reducing heating demand. The system was carefully coordinated within the constraints of the existing fabric, minimising visual impact while maintaining optimal performance.
To complement this, a network of wireless environmental sensors was installed, enabling real-time monitoring of temperature and humidity across the flat. This data-driven layer allows the building’s performance to be understood, tuned, and optimised over time.
The building itself carries significant architectural weight. Originally completed between 1959 and 1967 as Alexander Fleming House, it was designed by Ernö Goldfinger as the headquarters for the Ministry of Health. As his largest realised project, it embodies his post-war vision for high-density urban living - balancing tall structures with human-scaled environments. Its later conversion to residential use preserved this vision, but left considerable scope for environmental improvement.
Location: South London, Elephant & Castle, London Borought of Southwark
Property type: Multi storey residential appartment within a Grade II listed buidling
Scope of work: Our scope involved the comprehensive retrofit and reconfiguration of a 56 sqm, two-bedroom Grade II listed apartment at Metro Central Heights in London, originally designed by Ernö Goldfinger. We delivered full architectural services from concept to completion, including spatial optimisation, listed building consent, and coordination of all disciplines. The project adopted a fabric-first approach informed by Passivhaus principles, incorporating internal insulation, airtightness detailing, and thermal bridge mitigation, alongside the integration of a Mechanical Ventilation with Heat Recovery (MVHR) system and environmental monitoring. The result is a low-energy, high-comfort living environment achieved through careful alignment of heritage sensitivity and building performance.
Key Features
Fabric-first retrofit strategy informed by Passivhaus principles
Sensitive intervention within a Grade II listed apartment at Metro Central Heights, London
Internal insulation and airtightness strategy integrated within existing fabric
Targeted thermal bridge mitigation at junctions and slab edges
Installation of a Mechanical Ventilation with Heat Recovery (MVHR) system for continuous, efficient ventilation
Wireless environmental sensors for real-time monitoring of temperature and humidity
Spatial reconfiguration to optimise layout and usability within 56 sqm
Careful coordination of services within a constrained, heritage context
Project Results
Significant reduction in heat loss and overall energy demand
Improved thermal comfort with more stable internal temperatures
Enhanced indoor air quality through filtered, balanced ventilation
Reduced risk of condensation and moisture-related issues
Lower operational carbon and running costs
A quieter, healthier and more comfortable living environment
Extended lifespan and performance of a historically significant building
Demonstration of low-energy retrofit potential within listed modernist architecture originally designed by Ernö Goldfinger
