View of The New Cancer Centre at Guy's Hospital (Rogers Stirk Harbour Partners)

It's important that when buildings are built or refurbished they are made as energy efficient as possible, as they currently account for over 40% of the UK's CO2 emissions. Every year, the New London Awards recognise the best architecture in the capital, and in 2017 they again included a special Ashden Prize - for the most sustainable building among the hundreds submitted to the awards.

It’s rare to see an energy-efficient hospital, but The New Cancer Centre at Guy’s Hospital is this year’s worthy Ashden Prize winner. Meeting the complex requirements of a hospital while minimising energy consumption is no easy task, but architects Rogers Stirk Harbour + Partners, engineers Arup and consultants Stantec have made use of clever building layout, detailed sub-metering, daylighting, controlled solar gain and passive ventilation to achieve their goal. The result is a building that not only sets a new standard in energy use, but also improves comfort for patients and staff at the same time.

The New Cancer Centre at Guy’s Hospital uses an interesting financing model to enable such a high quality building to be constructed at almost no net cost to the NHS. Although part of the cost has been met by grants, the remainder is covered by four floors of the building being let out to a private hospital.

Other NHS Trusts can learn from the work at Guy’s and St Thomas’s – money spent on energy is money not spent on patients, and it is worth investing to save. Existing hospitals can take measures too, through behaviour change and retrofitting, as shown in the work of past Ashden Award winners Global Action Plan and University Hospital of South Manchester.

Ventilation ducts at The New Cancer Centre.

Highly commended

Alongside the winner, two other projects have been highly commended for the Ashden Prize. The Belarusian Memorial Chapel is the first wooden church built in London since the great fire of 1666, and demonstrates that one of the oldest building materials is still one of the best. Spheron Architects, Timberwright and Arup have created a building that is visually stunning yet goes well beyond minimum energy efficiency requirements. Using UK-produced wood for the frame of the building reduced energy used for transport, and the design of the building ensures energy consumption is minimised. The Chapel demonstrates that sustainability and beauty can go hand in hand, and should inspire the congregation worshipping there to consider the sustainability of other buildings they use.

The Belarusian Memorial Church in London (Joakim Boren).

Also using natural materials, the 121 new homes built at Dalston Lane have taken timber construction to new heights. Waugh Thistleton Architects and engineers XCO2 have built the world’s largest cross-laminated timber (CLT) structure, locking up a significant quantity of carbon and avoiding the embodied energy implicit in the use of steel and concrete. Using CLT at this scale demonstrates that it is a viable technology for large buildings, and shows the wisdom of the ‘timber first’ policy used by Hackney Council.

Not only does building with CLT have carbon benefits, it also simplifies and accelerates construction, reduces waste and results in a smaller number of deliveries of materials. Building with timber fits in with the ‘circular economy’, using natural products that at the end of their life can be re-used or recycled, and the weight saved by using timber allowed an additional storey to be added in comparison to a steel and concrete design, despite limits due to the HS1 train tunnel passing beneath the site.

There were of course many other worthy projects submitted, and it is reassuring to see that sustainable design is high on the agenda of many clients, architects and engineers in London.