From EPC D to future-proof: 3 Sheldon Square’s retrofit shows how re-using 30% of the MEP package cuts cost and carbon
When British Land set out to re-energise 3 Sheldon Square, an 11-storey, 13 000 m² office building at Paddington Campus, the brief was clear: create a diverse, vibrant, low-carbon workplace that would set the tone for refurbishment on the estate up to 2030 and beyond. Ramboll joined the team in 2020 as building-services, sustainability and smart-technology engineer, tasked with turning an EPC D development into a net-zero exemplar without resorting to the “strip-out and start again” mentality that dominates much of the London market.
Respect: Seeing value in what already exists
Although only two decades old, the building was underperforming. Gas boilers drove excessive energy use and carbon. The services plant was approaching its nominal end of life. However, the façade was in good condition, and the floor slabs, steel frame and core walls were fundamentally sound. Ramboll’s first step was therefore to respect the existing fabric, retaining the entire structure and envelope and, crucially, identifying which mechanical, electrical and public-health (MEP) elements could also live on.
Detailed surveys showed that pumps, pipework, sprinkler tanks, ductwork and large sections of the electrical infrastructure had service life remaining. By deciding early to refurbish and re-commission this equipment, rather than replacing it, British Land avoided the embodied-carbon burden of new steel, copper and plastics, while maintaining programme certainty in a volatile supply chain.
Review: Engineering Decisions Through a Sustainability Lens
Collaboration with Morris + Company, HTS, and building contractor 8Build was instrumental in bringing this vision to life. Ramboll applied its three-stage “Respect–Review–Renew” methodology:
Benchmark the existing operation against the British Land and wider emerging industry targets.
Stress-test multiple refurbishment scenarios against British Land’s sustainability brief, covering carbon, energy, biodiversity, wellbeing and social value.
Lock in the option that demonstrably met the most ambitious target in each category.
The option that won retained approximately 30–35 % of the MEP package by cost. Items such as main electrical switchboards, distribution, mechanical pipework and ductwork and sprinklers were overhauled, cleaned, and checked. While the more energy-intensive heat-generation plant was replaced outright with high-efficiency simultaneous heating-and-cooling heat pumps. Ramboll’s life-cycle model showed this hybrid approach delivered the lowest whole-life carbon of all the scenarios examined.
Renew: Delivering performance through circularity
The refurbishment was completed in 2024 and has since resulted in high leasing velocity for the entire building, with one tenant taking seven floors. This proves how thoughtful re-use can deliver new life into a building, making it attractive to future tenants.
Key successes in the retrofit include:
High-efficiency heat pumps now provide simultaneous heating and cooling, with fossil-fuel use removed and NABERS UK DfP 4.5* energy performance confirmed.
Electrical reconfiguration through re-use of electrical infrastructure with new smart meters to provide comprehensive monitoring of energy use without wholesale replacement.
Circular procurement through the Globechain initiative led to the re-use of materials from the strip out phase, contributing to a more sustainable and community-oriented approach.
Green biophilic balconies on the façade with cascading plants, delivering a 100% biodiversity net gain while offering tenants seasonal outdoor space that doubles as solar shading.
The social and wellness dividend
Sustainability on Paddington Campus is not confined to kilowatts and kilograms of CO₂:
BREEAM Outstanding, placing it in the top 1% of UK refurbishments.
WELL Building Standard precertification, confirming air quality, water purity, light, comfort and mental-health design principles.
WiredScore Gold, guaranteeing digital resilience for hybrid workstyles.
The project also channels British Land’s place-based social-value strategy through bringing local apprenticeships onto the site, and school STEM-outreach sessions led by the contractor 8Build and supported by the project team.
Lessons for the next generation of retrofits
Treat existing plant as an asset, not a liability. Pre-redevelopment and condition surveys frequently reveal more residual life than the textbook “20-year rule” suggests.
Integrate cost and carbon early. Ramboll’s whole-life model proved that the lowest-capex option was also the lowest-carbon option—a persuasive message for both finance directors and sustainability leads.
Collaborate across disciplines. A re-use strategy requires close collaboration between the project team. Re-using equipment will require 3rd patty validation, so ensure to programme this in a timely manner within the design stages.
Summary
3 Sheldon Square illustrates the quickest way to decarbonise a city is not to demolish and rebuild, but to respect, review and renew what we already have. By smartly re-using around one-third of its MEP equipment, the project shaved 30% off services capex, cut operational energy by 60%, and positioned itself for an EPC A, NABERS 4.5★, BREEAM Outstanding future, all while delivering vibrant terraces, richer biodiversity and a healthier indoor environment.
As corporate occupiers demand low-carbon, high-amenity space, and legislators tighten minimum-energy-efficiency standards, 3 Sheldon Square offers a replicable template by setting clear sustainability goals, letting data guide the refurbishment strategy, and never underestimating the value locked inside the plant room you already own.