CPW Supports St John’s College Oxford on its Journey to Net Zero
St John’s College Oxford has set out an ambitious Environmental Sustainability Plan that places decarbonisation at the heart of its operations. With a target to reduce scope 1 and 2 emissions across its central site buildings by 80% by 2035, as a key milestone on the pathway to achieving Net Zero Carbon, the College is tackling one of the biggest challenges faced by graded estates: how to balance conservation with urgent climate goals.
Why Net Zero, Why Now?
The College’s estate spans over 30 buildings, ranging from 15th-century halls to modern facilities completed in 2020. Many of these buildings are listed, with significant architectural and cultural value, yet their construction dates mean thermal performance and energy efficiency vary dramatically.
Recognising the impact of these inefficiencies on both carbon emissions and operational costs, St John’s has committed to a long-term transformation of its estate.
Prioritising the following:
A fabric-first approach: improving insulation, windows, airtightness, and reducing heat loss.
Transitioning from fossil fuels to clean energy: replacing carbon-intensive gas-fired systems with electrically powered, low-carbon alternatives such as heat pumps.
Heritage-sensitive upgrades: ensuring interventions respect conservation requirements while delivering real efficiency gains.
Phased, practical delivery: aligning carbon reductions with funding, operations, and student needs.
By embedding sustainability at the core of its estate strategy, St John’s College is not only responding to climate targets but also ensuring that its historic and modern buildings remain comfortable, efficient, and fit for purpose for generations to come.
A Roadmap to Net Zero
To translate these commitments into action, the College appointed a multidisciplinary team to deliver a strategic decarbonisation plan for its city-centre campus. CPW carried out extensive MEP surveys, thermal envelope assessments, and plant reviews across the estate.
Working closely with the College’s appointed heritage and masterplan architects, we developed a phased roadmap to reduce energy demand through fabric-first improvements before transitioning away from carbon-intensive gas systems. Our options appraisal explored decentralised and centralised heat pump solutions, alongside strategies for future energy centres, all evaluated against heritage sensitivities, operational impact, and carbon performance.
Read the full case study here.
Pusey Lane
At Pusey Lane, CPW is acting as Passive House Designer while also delivering MEP and acoustic services for a new mews development that will house 33 students.
The scheme comprises five townhouses and eight studios, designed to achieve Passive House – Low Energy Building Standard. Through careful daylight analysis, overheating mitigation, and integration of photovoltaic panels, the development is targeting a 40% improvement on 2021 Building Regulations CO₂ emissions.
This forward-thinking project will not only reduce operational carbon but also create bright, efficient, and comfortable homes for students in the heart of Oxford.
19–21 St John’s Street
CPW is also supporting the College in unlocking the potential of its historic estate. The retrofit of three Grade II listed Georgian buildings on St John’s Street is transforming inefficient student flats into low-carbon, high-comfort accommodation.
Using advanced thermal modelling and carbon analysis, our team is delivering a deep retrofit strategy that balances conservation with sustainability. Key measures include airtightness improvements, upgraded glazing, acoustic enclosures for heat pumps, and careful detailing to minimise thermal bridging.
The result will be a 40% reduction in heating demand and the removal of gas from the buildings – proof that heritage properties can achieve outstanding energy performance while preserving their character.
“We are excited to work with CPW; their innovative solutions have helped guide these projects to achieve high efficiency, low carbon design. These projects demonstrate our commitment to put environmental sustainability at the centre of all we do.”
Jonathan Pollard, Associate Director at CPW, added:
“The redevelopment of this historic area of Oxford is a major opportunity to showcase how listed and modern buildings can both achieve excellent energy performance without impacting heritage. Whether through Passivhaus or sensitive retrofit, we’re proud to support the College in setting new benchmarks for sustainable student living.”
The decarbonisation plan, Passive House led Pusey Lane development, and Georgian retrofits form a holistic approach to Net Zero – one that celebrates heritage, embraces innovation, and prioritises student wellbeing. With a phased roadmap through to 2035, St John’s College is setting a powerful example of how academic institutions can lead the way in sustainable transformation.
With over four decades of experience working across Oxfordshire, we understand the balance between protecting historic fabric and delivering modern, sustainable buildings. We’ve partnered with some of the region’s leading educational institutions, including Oxford colleges, to sensitively refurbish heritage sites and introduce low-carbon, future-ready systems.
Want to find out how we could support your decarbonisation journey? Visit our services page.