Nestled in the heart of one of London’s busiest shopping districts, The Crown Estate’s 7 Air Street is the first Grade 2-listed building ever to achieve the notorious BREEAM 2011 Outstanding rating and is the highest-scoring office scheme against current BREEAM standards.

Now recognised as the UK’s most sustainable historic building, this 46,000sq.ft office refurbishment – completed in 2015 – forms part of The Crown Estate’s £1bn investment in its Regent Street portfolio.

The seven-floor property’s laundry list of energy efficiency technologies and green initiatives reads like a catalogue of sustainability excellence for building professionals, with no stone left unturned by The Crown Estate’s development and project management team.

7 Air Street is connected to a unique central energy centre powered by fuel-cell technology, which saves more than 350 tonnes of carbon emissions each year while providing power to 500,000sq.ft of commercial and residential accommodation along Regent Street. Low-energy air conditioning, LED lighting and 23kW rooftop solar panels add to the scheme’s energy efficiency initiatives, while and a highly-effective building envelope drastically reduces its heating and cooling requirements.

The building’s outstanding green credentials don’t stop there. Additional sustainability features include extensive bicycle provision to promote worker health and wellbeing; and an ecological roof which is designed to attract insects, birds and bats, and offers workers the opportunity to enjoy outdoor spaces during the day. The species-rich green roof forms part of The Crown Estate’s ongoing ‘ecology masterplan’, which will see the asset management firm deliver a hectare of new green space across its West End portfolio.

For The Crown Estate, this project has preserved and extended the usable lifespan of two listed buildings, massively enhancing occupier appeal and contributing to rental value and let-ability – 7 Air Street was 80% let just eight weeks after its completion, exceeding all expectations.

The Estate has struck a perfect balance between updating a building for the needs of today’s customers; upgrading sustainability performance, and maintaining historically significant features. The organisation has moved beyond the low-hanging fruits of energy efficiency towards some truly amazing low-carbon innovations; considered everything from energy efficiency and staff wellbeing right through to ensuring that construction workers were paid Living Wage or more during development.

In fact, it’s hard to think of any green box this building doesn’t tick, making 7 Air Street the jewel in the Crown Estate’s progress on sustainability.

Judges’ comments

The Crown Estate’s Grade-2 listed refurbishment project pushes the boundaries of what’s possible in green building development. Scoring highly across all criteria, 7 Air Street is a really impressive retrofit development that was delivered within very tough constraints. The Crown Estate demonstrated good use of the latest innovate technologies and took a very holistic approach to this project, which will undoubtedly have a great influence on heritage properties across the country. 

Sustainable Building of the Year: Meet the finalists

Costa Coffee

Setting a new standard for green building design, Costa’s ‘Eco Pod’ was the first ‘zero-energy’ coffee shop in the UK. This ‘zero energy’ is achieved through passive ventilation and innovative construction techniques which means the energy required to heat and cool the building is minimised. The low amount of energy that is required for building temperature control will come from solar PV cells embedded in the specially curved roof.

EDF Energy

Energy giant EDF’s new Cannington Court Campus – a former 12th century priory in Bridgewater – has delivered an on-site energy centre and now acts as a demonstration test bed for the retrofitting of low carbon technologies to older buildings. The project provides all heating, cooling and domestic hot water (DHW) for the EDF site and satisfies Grade 1-listed building restrictions, proving that ultra-low-carbon solutions are technically and economically viable for commercial premises.


Engineering consultancy Cundall set out to make its new London office at One Carter Lane a first-class green building fit-out that would showcase the possibilities of cutting edge sustainable design. This fit-out is unique in being the first building in Europe to register for the WELL Building Standard certification – arguably the highest international recognition of buildings that put the health and wellbeing of the occupants at the heart of design.

Nottingham Trent University

Nottingham’s impressive Pavilion building was designed to be as energy efficient as possible, using Passivhaus principles that the University is adopting across all of its projects. This resulted in the building receiving an Energy Performance Certificate (EPC) carbon-negative rating of A+. Built with great insulation properties, the Pavilion retains heat to keep it warm in the winter and stays cool in the summer, also including a huge 96kW array of solar panels on its roof.

Fraser Brown MacKenna Architects

London-based Frazer Brown recently completed a £29m refurbishment of the Cockcroft Building at the University of Brighton – one of the largest academic retrofit projects in the UK. Unlocking the hidden value of the existing 10,500m² building, its environmental potential was significantly enhanced by Frazer Brown with the latest green technology. Stand outs include an aquifer thermal energy store which led to a 57% reduction in energy demand; 59% reduction in C02 emissions; and fuel savings of £82,000 a year.


Built for the Saudi Basic Industries Corporation (SABIC), the ‘Home of Innovation’ facility serves as a green beacon for what can be achieved in one of the world’s harshest climates. SABIC’s commitment to sustainable building performance resulted in energy and water savings of at least 40%. The construction diverted more than 90% of construction waste away from landfill and used a significant percentage of recycled sustainable materials in a variety of construction applications.

UK Energy Partners

Chalgrove Primary School in Greater London needed a new Schoolhaus for their ‘bulge’ Reception class. UK Energy Partners dually delivered what has become an exemplar for best practice in sustainability and low-carbon building design within the education sector. The Schoolhaus is the UK’s most energy efficient school building, with an EPC rating of A+ (-83), and zero running costs. Lighting, heating, and cooling systems are all powered by the school’s roof-mounted solar panels.

edie staff

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