Silbury House, Milton Keynes achieves A+ rating after EPC revalidation
Silbury House in Milton Keynes has achieved an EPC A+ rating following a Level 5 EPC revalidation – the highest EPC classification for a commercial building in the UK.
The A+ rating signifies a property that generates as much or more energy from renewable sources than it consumes and owner RO Real Estate is celebrating Silbury House’s place in the premier league of office buildings capable of operating at net-zero carbon or better.
Silbury House underwent major refurbishment in 2024, achieving BREEAM Outstanding, RESET Air Quality Certification and the highest Fitwel rating of 3 Stars. 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. RO is now targeting NABERS 5 Star for the building, and has also enrolled it on the WELL Performance Rating.
Ana Bajri, Head of Sustainability at RO Real Estate, said:
This 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…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.”
The measures on the building include roof-mounted solar PV, LED lighting with intelligent controls, a VRF heating and cooling system, and mechanical ventilation with heat recovery (MVHR) which supports internal air quality while reducing energy demand.
Sam Maddock, Director at Sustainable Urban Solutions, said:
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+.”
