Silbury House achieves net-zero energy performance
RO Real Estate is delighted to announce that Silbury House, Central Milton Keynes’ most sustainable office building, has achieved an EPC A+ rating following a detailed Level 5 Energy Performance Certificate (EPC) revalidation, signifying that the building’s operational carbon impact is net-zero.
An EPC A+ rating is the highest possible classification for a commercial building in the UK, signifying a property that generates as much or more energy from renewable sources than it consumes. Achieving this level of performance places Silbury House among a very small number of office buildings nationally capable of operating at net-zero carbon or better, demonstrating exceptional operational efficiency and long-term resilience against tightening environmental regulations.
Completed in 2024 following a major refurbishment by RO Real Estate, Silbury House has been designed with sustainability, occupier wellbeing and operational performance at its core. The building already holds leading environmental and wellbeing credentials including BREEAM Outstanding, RESET Air Quality Certification and the highest Fitwel rating of 3 Stars. It is targeting NABERS 5 Star, and is also enrolled on the WELL Performance Rating, positioning Silbury House as a flagship sustainable workspace in Milton Keynes.
The upgraded EPC assessment, completed by Sustainable Urban Solutions, reflects the impact of a range of low-carbon technologies and design features integrated throughout the building. These include roof-mounted solar photovoltaic panels generating renewable energy on site, high-efficiency LED lighting with intelligent controls, a variable refrigerant flow (VRF) heating and cooling system, and mechanical ventilation with heat recovery (MVHR) which supports internal air quality while reducing energy demand.
Ana Bajri, Head of Sustainability at RO Real Estate, commented:
“Silbury House achieving an EPC A+ assessment is a clear demonstration of our sustainability strategy being delivered in practice. As a responsible, long‑term landlord investor, our focus is on maximising the performance of existing buildings through targeted, data‑led retrofit and optimisation strategies. By prioritising on‑site renewable energy through Solar PVs, electrification and optimisation of HVAC systems, EV charging infrastructure and well‑planned, low‑carbon refurbishments, we are materially reducing operational energy demand and emissions while enhancing asset resilience.
“The lessons from Silbury House, which is now the only office building with an EPC A+ rating in Milton Keynes, will be scaled across our portfolio, accelerating delivery of our net-zero pathway and improving asset performance.
“This approach is about future‑proofing our portfolio, protecting value and delivering high‑quality, sustainable workplaces that support occupier needs and meet evolving regulatory expectations.”
Sam Maddock, Director at Sustainable Urban Solutions, commented:
“As a business, we’ve made a conscious decision to focus on Level 5 EPC modelling because we believe it delivers a more accurate and valuable outcome for clients. A higher level of technical scrutiny allows us to properly evidence building services, challenge assumptions and ensure that high-performance design features are fully reflected within the model.
“This building already had strong sustainability fundamentals, from its all-electric strategy to LED lighting, VRF, MVHR and on-site solar PV. The Level 5 approach ensured those features were correctly captured, which directly supported the move from an A rating to A+.
“Achieving an A+ EPC is a significant success, and it reflects the quality of the building’s design and operation.”