Sustainability Report

Plant is a heritage-led retrofit, focusing on the repair, refurbishment, and regeneration of a Grade II listed office building and its gardens. At Plant, the harmonious blend of heritage conservation, modern functionality, and environmental responsibility sets a new standard for commercial workplace redevelopment.

Targeting BREEAM Outstanding and WELL Platinum certifications

Plant is targeting BREEAM Outstanding and WELL Platinum certifications. The project balances operational costs and performance with a number of energy-efficient solutions, including enhanced insulation, triple-glazed windows, and renewable energy systems.

Embodied and operational carbon

Embodied and operational carbon were minimised by adopting a thoughtful approach to the existing structural fabric. A detailed understanding of the building’s structural principles and behaviour allowed the team to limit structural interventions while simultaneously maximising the potential for refurbishment within the existing structural fabric. These limited interventions resulted in an exceptionally low embodied carbon rate per square metre, reflecting the project's sustainable design approach.

Actual figures can be made available after twelve months, but modelled values are outline here:

Energy consumption (kWh/m2/yr): LETI value: 55 / Plant value: 39

Heating demand (kWh/m2/yr): LETI value: 15 / Plant value: 14

Lighting power (W/m2): LETI value: 4.5 / Plant value: 5

MVHR heat recovery: LETI value: 90% / Plant value: 95%

Heat pump min SCOP: LETI value: 2.8 / Plant value: 4.5

(LETI — Low Energy Transformation Initiative — is a voluntary network of built environment professionals, established to support the transition of the UK’s built environment to net zero carbon.)

Added value, sustainability, and efficiency

The project incorporates a number of initiatives aimed at providing additional value to stakeholders while simultaneously promoting sustainability and efficiency.

• To preserve the building’s architectural character and reduce material waste, its facade frames, travertine, and engineering brick wall finishes are retained.
• During the demolition phase, steel beams were evaluated for reuse as trimmer beams in the new BWH slab penetrations, saving on material costs and reducing environmental impact.
• In office areas, carpets and small power installations are omitted to accommodate tenant-specific fit-out requirements. This minimises unnecessary expenditure and prevents potential wastage.
• Existing service lifts are retained, their extended lifespan avoiding the environmental impact of replacement.
• A glass recycling programme repurposed materials from demolition works, contributing to the project’s environmental goals and responsible resource management.
• Full-height glazing and high-performance curtain walls maximise natural light, reduce glare, and improve energy efficiency. This is complemented by passive shading from recessed facades.
• All-electric systems, variable refrigerant flow (VRF) technology, optimised air handling, and demand-driven controls contribute to reducing operational carbon emissions. Smart building management and water conservation features further enhance efficiency, resulting in an eight percent improvement over Part L Building Regulations. (Part L of the UK Building Regulations relates to the conservation of fuel and power.)
• Intuitive systems optimise heating, ventilation, and air conditioning, balancing comfort with energy savings.
• Real-time CO2 sensors adjust fans and pumps dynamically, using energy only when required. 
• VRF technology redistributes heating and cooling efficiently, reducing waste.
• High-performance LED lighting equipped with daylight dimming and occupancy-based controls reduces energy consumption. 
• As part of the retrofit, the building is now fully electric. Rooftop photovoltaic panels supplement the power requirements in common areas. Eighty car parking spaces are available with EV charging points.
• The garden terraces cover around 3,216 square meters. Plant species that are ill-adapted to exposed rooftop conditions have been replaced by native and non-native plants that are drought tolerant, suited to open conditions, and require minimal irrigation. This fosters improved biodiversity, helping pollinators and foragers to flourish.
• Over 22,500 new plants were introduced as part of the project, together with 86 new trees that complement the existing trees on the site. The landscape scheme delivers a 12.79 percent biodiversity net gain. 
• The terraces contribute to rainwater harvesting. Rainwater is collected and utilised to irrigate the gardens, thereby reducing the reliance on potable water. A drip line irrigation system is employed for this purpose. Trees have been strategically positioned to offer natural shade and shelter.
• To ensure efficient upkeep, the design incorporates additional access hatches for ongoing MEP maintenance and modular components for easy replacement.