Sustainability Report
Embodied carbon
Archello: Were any sustainability certifications or performance standards part of the process, formally or informally?
Max Dewdney, Director at Studio DERA: The Pool was an unusual retrofit project, but our design process was guided by best-practice sustainability frameworks, including LETI, the RIBA 2030 Climate Challenge, and Department for Education energy performance standards for educational buildings. These benchmarks shaped our approach to fabric upgrades, energy systems, and whole-life carbon reduction. The project targets a whole-life carbon footprint below 600 kgCO₂e/m² over sixty years, in line with LETI’s 2030 retrofit benchmark.
Archello: Beyond what’s visible in the design, were there particular strategies that helped reduce the project’s embodied carbon footprint?
Max Dewdney: Yes — our biggest carbon saving came from adaptive reuse. Retaining the existing swimming pool structure avoided demolition and removed the need for high-carbon concrete and steel, saving an estimated 500–1,000 kgCO₂e/m² compared with a typical new-build teaching space.
Embodied carbon (A1–A5 estimate): 300–400 kilograms kgCO₂e/m², achieved largely through extensive reuse of the existing structure and minimal new structural intervention.
Sustainable materials/systems
- High-performance glazing: Triple-glazed units (U-value 1.0 W/m²K, G-value 0.4) balance daylight with controlled solar gain, which is critical for a deep and formerly windowless pool hall.
- Timber-based interior architecture: All new joinery, seating, and perimeter desks are made from sustainably sourced timber. Timber provided the lowest embodied carbon option at approximately 400–500 kgCO₂e/m³, while bringing warmth and acoustic softness to the space.
- Low-carbon mechanical systems: A fully electric system powered by air source heat pumps eliminates fossil fuel dependency.
- Recycled acoustic products: Acoustic treatments made from recycled paper and recycled plastic reduce reverberation and demonstrate circular material reuse.
Operational Emissions / Energy
Archello: Were there particular strategies that helped reduce the project’s operational carbon footprint?
Max Dewdney: Passive measures were central. A high-performance envelope (0.15 U-value walls, triple glazing at 1.0 U-value with a 0.4 G-factor), brise-soleil shading, and mixed-mode ventilation all reduce heating and cooling loads. The building is now fully electric, with air source heat pumps providing heating and cooling. LED lighting with daylight dimming and occupancy sensing further lowers operational energy. Future overheating is mitigated through shading, mixed-mode ventilation, carefully balanced glazing ratios, and the thermal mass of the original pool structure. Daylight, internal and external planting, timber materials, and acoustic comfort were prioritised to create an uplifting learning environment that supports wellbeing and concentration.
Predicted operational energy
- Regulated: 55–65 kWh/m²/yr
- Unregulated: 15–25 kWh/m²/yr
- Total: approximately 70–90 kWh/m²/yr, in line with LETI’s target of under 100 kWh/m²/yr for deep retrofit in education.
The building is fully electric and designed to be compatible with future on-site renewables.
Afterlife
Archello: Was the design shaped by principles of longevity or circularity—adaptability, reuse, durability?
Max Dewdney: Absolutely — the entire project was conceived as a long-life, loose-fit retrofit. The primary structure, pool shell, and external walls were all retained, significantly reducing embodied carbon. New interventions, including the multi-use stage, perimetre benching, and joinery, are demountable and reconfigurable, allowing the space to adapt to future pedagogical needs. The open-plan, column-free volume supports multiple modes of teaching, independent study, performances, exams, and community events. Durable materials, electric-only systems, and replaceable components support a design life of at least sixty years.
Key products in low carbon design
