Sustainability Report

Sustainability information provided by O’Sullivan Skoufoglou Architects

Embodied carbon overview

• The primary strategy for reducing embodied carbon was the careful repair and retention of the existing building fabric. By avoiding demolition and the introduction of steel or a new concrete ground slab, the project reduced the emissions typically associated with reconstruction while enabling the building to meet current legislation standards.
• New construction was executed almost entirely in timber, including the new dormer and the structural strengthening of floors and openings. Steel was avoided where possible, while repair strategies were carried out selectively to reintegrate the existing structure into continued use rather than replacing it.
• A high proportion of the materials specified for the refurbishment are naturally low-carbon or carbon-neutral, including wood-fibre insulation, timber panelling, and reclaimed materials salvaged directly from the site. British-made materials and local suppliers were prioritised to reduce transportation-related emissions and support local supply chains.
• Specified products and systems include bespoke timber windows by Original Sash, wood-fibre insulation by STEICO, wood-wool panels by Troldtekt, Okoume plywood wall linings, and Douglas fir plywood flooring.
• The project recorded an upfront carbon figure of 137 kgCO2e/m² and an embodied carbon figure of 191 kgCO2e/m², placing it below commonly referenced UK low-carbon benchmarks established by LETI and the RIBA 2030 Climate Challenge.
• The carbon footprint breakdown was calculated using the FCBS CARBON tool issued by Feilden Clegg Bradley Studios (FCBStudios) under an international Creative Commons licence. The upfront carbon calculation covers RICS Modules A1–A5, while the embodied carbon calculation covers Modules A1–A5, B1–B5, and C1–C4.

Operational emissions overview

• The refurbishment incorporated double-glazed timber windows, wood-wool insulation, plywood wall linings, and a vapour-permeable airtight roof build-up alongside upgrades to the thermal performance of the existing structure.
• Natural light and cross-ventilation support the environmental performance of the interior spaces.
• Provision has been made for future adaptations, including infrastructure for a Sunamp thermal energy store, roof cabling for solar panels, and systems designed to accommodate evolving technologies.
• Predicted energy use for the house is 105 kWh/m²/yr, while actual energy use is recorded at 95 kWh/m²/yr.