Sustainability Report

Embodied carbon overview

• The project’s embodied-carbon strategy is centred on retaining and upgrading the existing 1820 brewery fabric rather than replacing it. SIRS Architects minimised demolition, retrofitted the existing structure, and reused materials wherever possible, including windows, roof slates, granite cobbles, brickwork, floorboards, timber joists, and beams. The courtyard also reused 155 square metres of granite cobbles, which were lifted from their concrete bed and relaid on gravel. 
• Where new materials were required, recycled, reclaimed, local, and natural options were prioritised, including recycled gypsum board, reclaimed brick, Welsh slate, English oak, London clay brickwork, and Portland stone. 
• New construction was approached through material efficiency, with steel and timber used where possible as alternatives to reinforced concrete. Diagonal bracing was adopted for the pavilion and superstructure to reduce the amount of steel required compared with moment-frame construction. 
• A layer of recycled-glass external insulation was also installed between the 57 perimeter underpins and the new basement structure, supporting the retrofit of the existing fabric while introducing recycled content into the envelope build-up.

Operational performance

• The original building envelope was insulated in line with current regulations, while existing rooflights were sealed to improve airtightness and thermal performance. Existing windows were fitted with low-e double glazing and blinds or curtains to reduce solar heat gain, while reduced solar radiation admittance helps prevent overheating and protects artworks, which are limited to a maximum exposure of 250 lux.
• A new airtight extension with high thermal mass helps maintain stable internal conditions, reduce cooling demand, and prevent overheating. Areas including the stairwell, reception, caretaker’s apartment, and staff meeting room are naturally lit, reducing reliance on artificial lighting during the day. 
• The building’s fabric performance values, covering both the original 1820 structure and the new side and basement extensions, include a roof U-value of 0.16 W/m²K, exterior walls at 0.25 W/m²K, exterior windows at 0.1 W/m²K Uw, and the ground floor at 0.15 W/m²K Uw. The average building U-value is 0.2 W/m²K.
• Active systems include a Building Management System with temperature and weather compensation to optimise energy use, alongside low-energy LED lighting with presence detection and automated controls. 
• The project reports predicted energy use of 113.76 kWh/m²/yr and actual energy use of 81.13 kWh/m²/yr. 
• Annual operational CO2 emissions are reported at 16.27 kgCO2/m², calculated according to 2022 Building Regulations. Gas is used on site, with reported consumption of 51.58 kWh/m²/yr. The project does not include on-site renewable energy generation and is not connected to a district heat system.

Biodiversity and water

• The external courtyard has been designed as a self-sustaining ecosystem. Twenty-six plant species and two four-metre-high trees were planted, enhancing biodiversity and supporting carbon capture. New planting beds along the courtyard walls increase the amount of greenery and improve the site’s overall environmental performance.
• The plants are entirely irrigated using a rainwater harvesting system, which stores water in an underground tank. Permeable courtyard paving contributes to sustainable urban drainage and reduces flood risk: 155 square metres of granite cobbles were removed from their concrete bed and relaid on a gravel bed.