Ensuring building air quality and pedestrian comfort at a major biomedical facility
Located in central London, the Francis Crick Institute is one of Europe’s largest biomedical and translational research centers, spanning more than 980,000 sq. ft. and housing over 1,500 staff. The Institute is a partnership of six leading medical research and educational organizations – the Medical Research Council, Cancer Research UK, the Wellcome Trust, University College London, Imperial College London and King’s College London – and is designed to facilitate collaboration among researchers working across a range of fields from biology to physics to computer science. The building occupies a full city block in the heart of London, just north of the British Library.
Pedestrian Comfort and Safety.
The building’s architects, HOK, wanted to ensure that it would be a neighbourly presence at street level, despite its large scale. We were engaged to help the Institute be friendly not just visually but also in the way it affected the wind environment for pedestrians. London is a challenging environment for building designers because of its density; the city’s planning policies aim to make the impact of any new building on pedestrian wind conditions “negligible.” For this reason, planning exercises for any building must carefully consider the safety and comfort of people on the street. Pedestrians were an especially important consideration at the Francis Crick site because there would be so many of them: the facility is located near King’s Cross St. Pancras Station, London’s second busiest Underground hub.
Building Air Quality.
One of the facility’s most striking design features is its roof: a porous structure composed of two long, curving shells that enfold the building from each side. These shells conceal the building’s heating and cooling units and incorporate solar panels. The designers came to us for wind tunnel studies that would help them optimize the design of the facility’s exhaust stacks so they would interact effectively with the roof structure, promoting the dispersion of exhaust and reducing any risk of exhaust re-entering the building’s air intakes.
We began by making sure we had a deep understanding of both the designers’ aesthetic objectives and their building-performance priorities for the Institute. We then performed boundary layer wind tunnel testing that gave the building’s designers confidence that the Institute would perform safely and efficiently in these two key respects:
Pedestrian Comfort and Safety.
To determine whether pedestrians near the new building would experience wind flows that were comfortable or excessive, we began by gathering local meteorological data for all seasons. Using a scale model of the building and its surroundings, we simulated a wide range of expected weather in our wind tunnel and quantified the conditions nearby pedestrians would experience, including at the building’s entrances. This process allowed us to offer evidence-based confirmation to the building’s designers that, once the structure was complete, pedestrian conditions in the neighbourhood would remain comfortable. It also let us propose recommendations that would make a few locations where pedestrians were likely to linger – such as a nearby taxi stand – more hospitable in winter.
Building Air Quality.
The designers had to ensure the safe dispersion of exhaust from laboratory fume cupboards, animal holding rooms, a combined heat and power (CHP) plant, and kitchen cooking hoods. The laboratory’s location in a dense urban area made it especially important to disperse exhaust safely away from neighbours.
We intended to use a detailed tracer gas dispersion study to understand how the exhaust stacks would perform. But the insights we drew from this study would only be as accurate as the scale model of the building. Because of the roof’s intricate design, it was important to evaluate the performance of the roof exhaust stacks using an extremely precise building model capable of capturing the nuances of the structure’s behavior. So we constructed our scale model using stereolithography (SL) technology, a process that converts liquid plastic into solid models from 3D building drawing information. This technology let us accurately capture the fine details of the curved and porous roof, which we anticipated would have a significant influence on localized wind flow behaviour and on the exhaust stacks’ performance.
Our tests revealed that the porous roof structure was advantageous for wind flow over the building and the resultant dispersion levels from the exhaust stacks. This discovery let us recommend an energy-saving design adaptation. If the roof design would make the wind do extra exhaust dispersion work – and our testing had shown that it would – that meant the designers could let exhaust exit the rooftop stacks at lower velocity. Operating the fans at a slower pace would yield long-term energy savings.
The Francis Crick Institute was completed in August 2016. It quickly earned Building Research Establishment Environmental Assessment Method (BREEAM) Excellent certification, as well as praise from urban design enthusiasts. Wallpaper magazine called the building one of the world’s most striking new structures of 2016 in a review titled “Science chic.” The Institute now functions as a flagship for UK biomedical science. We’re proud that our work contributed to the design team’s confidence that the building will operate safely and comfortably in its bustling urban context, while the occupants within focus on innovation and discovery.