Air pollution soup kitchen offers food for thought
A pop-up installation at the London offices of the Royal Institute of British Architects (RIBA) is serving soup that is colour-coded to reflect air pollution levels. Pea Soup House offers free soup ranging from green pea when the air quality is good according to the Daily Air Quality Index (DAQI), through to squash or red pepper, and finally beetroot and horseradish as it declines. The pop-up’s structure, which is made from sustainable materials, is covered in coloured wooden batons that represent daily readings of air pollution from Oxford Street last year. There are also information boards presenting research from experts at King’s College London (KCL). In 2015, KCL published research indicating that 9,500 people in the capital die prematurely each year due to air pollution.

“I see the air is good today,” says the security guard, as he sips his cup of bright green pea soup. “I can tell by the flavour.”



Staff and visitors here at the central London headquarters of the Royal Institute of British Architects (Riba) have been treated to daily free soup from the Pea Soup House, a pop-up installation in the lobby that serves colour-coded soup which matches the government’s Daily Air Quality Index (DAQI).

Pea Soup House menu Photograph: Pea Soup House

Flavours start with pea soup - green for good air quality, then move to yellow butternut squash or red pepper and chilli as the air gets worse, and an eye-watering purple beetroot and horseradish flavour when the pollution is high.

Since its launch last week, the kitchen has given away around 50 cups a day, and so far they’ve all been green. “I need to find a way to jazz it up a bit with this good air,” jokes the chef, Angeletia Clarke.

Prize money from a Riba competition enabled seven young architects from Feilden Clegg Bradley Studios to design and build the installation, which aims to bring people together through food and raise awareness of air pollution through the unlikely medium of soup.

“People might come to Pea Soup House not knowing much at all about air quality, or just say ‘free soup, brilliant’ – but that for us is a way into a wider discussion,” says architect Chris Allen.

“The soup means people can connect that day to air quality and start to make those links themselves,” explains researcher Joe Jack Williams.

As well as serving as a soup kitchen, the structure is designed to communicate a whole year’s worth of air quality data in a way that people can easily see. It’s clad in brightly coloured horizontal wooden batons that each represent individual days of 2015 air quality readings from Oxford Street, one of the most polluted streets in London. Small plaques indicate the dates and there are information boards with data and research from air quality experts at King’s College London.

“We had all sorts of great data and research and we were trying to work out how we could represent that through architecture,” said Allen. “We had what we felt was a very strong idea – linking soup and the daily air quality index – but how would that be expressed in architecture? We talked about handing soup out on the street but we decided that actually it needed to be grounded in a place, and feel like it’s arrived in a community.”

Chris Allen (left) and Joe Jack Williams (right), two of the team involved in the construction of Pea Soup House. Photograph: Sarah Lee/The Guardian

Inspiration for the project came from “pea souper”, the term coined by John Sartain in 1820 to describe the deadly, thick yellow smogs of London.

“That was the starting point for us when we were thinking about how to engage people,” said Allen. “We can make that connection to air quality today and the history about pea soup fog. Britain was the first country in the world to look at air quality and that first step of [the Clean Air Act] in the 1950s is the start of air quality as we know it.”

A study by King’s College London last year found that nearly 9,500 people in the capital die early annually because of air pollution. Earlier this year it took parts of London just one week to breach annual limits, and a major global study by the World Health Organisation in May found the city breached its guideline limits for two harmful types of particulate pollution.



The UK government is facing renewed court action from campaigners over air pollution, some of which has resulted from the rise in the number of diesel cars on the road, and the repeated breaches of EU limits on pollutants.

London’s air quality is particularly bad on naturally foggy days, as polluting particles tend to increase the intensity of the fog. Photograph: Guy Bell/Alamy Stock Photo

London’s recently elected mayor, Sadiq Khan, has made improving the capital’s air quality a top priority. Within a week of his election last month, he unveiled plans to more than double the size of London’s clean air zone and retrofit 1,000 more buses with clean technology. He has also proposed bringing forward an extra charge on the most polluting vehicles to 2017.

Last month Khan announced he would join the high court challenge against the government over its failure to tackle the problem.

“I think air pollution is an invisible problem and people know it’s there but they don’t quite know the root cause, how it occurs or what they can do,” said Williams. “I think Pea Soup House is really about building that awareness so people can really start to ask for better air quality and say ‘I saw that the soup is purple today, what’s causing it, what can I do about it’?”

Pea Soup House is built using low-cost, carbon-neutral materials, wood from sustainable sources, low chemical paint and varnish, no solvent and with recycling and onward use in mind. The plan is to eventually move it to different pollution hotspots and raise awareness in further communities, possibly engaging schoolchildren by repainting the batons according to their local pollution levels.

“Now we know it works and we know it’s really engaging people we can build it somewhere with a bit more visibility,” said Williams.



Angeletia Clarke serves up pea soup on a day with low air pollution levels. Photograph: Sarah Lee/The Guardian

“At the moment this is the first step for us, we want to reach out to communities and experts and put what we learn back into planning as an architect and complete that cycle,” said Allen.

The soup comes from Clarke’s Kitchen, a small family-run catering company that uses organic, seasonal ingredients, some of which comes from local allotments or food that is destined for waste.

“I came up with all the different flavours I could do according to the colour code,” said Clarke, who is also an architecture student. “Everything is French-Creole inspired, with my own seasoning and recipes.”

Cathy finishes her cup and heads back to work. “The soup is delicious,” she says. “I’m quite uncomfortable to say that I’m looking forward to the air being slightly worse so I can try I a different soup, although I don’t think that is really what the project’s aiming for!”