But really, they should be dealing with the source of the problem.
When Alex Johnson tipped me off about an Independent article, ‘Living walls’ should be installed to help most polluted schools, campaigners say, I rolled my eyes. So much pollution from so many cars and HGVs (heavy goods vehicles, what they call big trucks) and Laurie Laybourn-Langton, director at UK Health Alliance on Climate Change tells Sky News:
Yes, but the first thing we should be doing is eliminating the problem, not trying to mop it up. Laybourn-Langton knows this, also saying:
For schools, measures like living walls can help to improve the quality of air children breathe and therefore improve their health and well-being, enhance the look and feel of their environment and also educate them about air pollution and climate change.
However, the responsibility of cleaning up our air lies with government, which has the power, resources and duty to respond. Primarily, this requires the government to introduce new laws.
Laws like banning cars near schools, and getting the dirtiest cars and trucks off the road. Instead, some schools like St. Mary’s Primary School, Chiswick are crowd-funding to buy living walls and install air filters in classrooms. Even the Mayor is hopping on the bandwagon, pledging £32,000 if the community can raise the rest of the cost of the wall. According to the funding site, the project will cost about £75,223 and they have already raised £54,765.
The plan is to install the wall on top of an existing brick wall in the playground; the renderings are quite lush. It would be rude of me at this point to say that it makes no sense to do this; living walls are expensive to buy and expensive to maintain, because plants tend to want to live in the ground. Look what happened to the first living wall in London.
That's why French architect Édouard François builds green facades instead of living walls, where "a structure fastened to the wall provides a trellis for vines and climbers planted in the ground or in containers." In this case, they would just take a few feet of the playground and plant it intensively. Instead of a sea of asphalt, put in a garden.
The other big question I have always had is, do they work at cleaning the air? Here, the evidence is pretty clear that, when built inside, living walls actually do remove carbon dioxide and reduce the amounts of volatile organic compounds. In his thesis, Ivan Cheung of the University of British Columbia found that living walls removed up to one third of the CO2 and sucked up VOCs. But that was inside a test chamber; this is in the great big dirty outdoors.
In the end, perhaps the most significant difference this wall will make is that it gives the kids something green to look at, and it will be a much nicer environment. As the funding site notes,
Apart from the obvious long-term benefits to the health of the children, we believe that the embellishment of the area will have a positive effect on the day to day lives of the local community. It would also revive a very large space which at the moment is slightly wasted and "very sad looking" and become a beautiful green oasis with at its centre a grandiose living wall.
It's also amazing that they have been able to raise so much money towards it. But it isn't going to make much of a difference. For that, they have to get rid of the cars that are causing the problem; they have to cut it off at the source instead of trying to stick on a band-aid, or a plaster, or whatever they call it in London.