People are leaving London due to air pollution: we are the problem

It is not just moving vehicles in London that are the problem – 2.7 million privately owner parked cars take up £172bn of land.

There are 868 car parks in London within a mile of a train or tube station, 400 of which are owned by local authorities and on which 80,000 new homes could be built, research by property group JLL reveals.

Nick Whitten, author of the study The Direction of Travel for Automotive Real Estate, suggests that privately-owned diesel or petrol cars should be phased out of city centres and the roads put to a cleaner use.

A child inside a car on the daily school run is more exposed to fumes than a cyclist speeding down Piccadilly

Rather than a network of unhealthy arteries clogged up with traffic, Whitten’s sketch of the future cityscape has roads replaced with wider cycle lanes, linear parks, canals and tree trenches (long sunken beds for trees and foliage that absorb excess rainwater while naturally filtering the air).

His vision is littered with living walls, CO₂ absorption plants, smart bike storage and chargers for electric cars. Whitten foresees e-bus fleets that change route depending on where wannabe passengers are waiting and electric car sharing schemes “a bit like shared Uber on-demand”.

What is better than electric cars? No cars. E-vehicles do not emit exhaust fumes but they still produce large amounts of tiny pollution particles from brake and tyre dust, for which the government already accepts there is no safe limit. “Fewer cars, not cleaner cars are the answer,” says government advisor Professor Frank Kelly.

Cars are not the only contributing factor to the air quality crisis, however. “The built environment is responsible for 37% of nitrogen oxide emissions,” says energy and sustainability expert Barny Evans, technical director at engineering firm WSP.

If Whitten is advocating turning over space taken up by parked cars to house builders, construction must get cleaner, too.

There are 400 car parks in London within a mile of a train or tube station owned by local authorities on which 80,000 new homes could be built, research by JLL reveals

There have been improvements in the industry, explains Gary Fuller, author of The Invisible Killer: the Rising Global Threat of Air Pollution – and How We Can Fight Back. He is leading a working party between the Mayor’s Office, King’s College and councils including Camden, Islington and Lambeth to lower emissions from the construction industry. “We no longer use wrecking balls to demolish buildings. Machinery that nibbles away at the concrete, reducing dust significantly, is now used,” he says.

Smedley cites Delhi as one of the worst cities he has visited for unregulated and polluting construction sites. “Uncovered piles of cement and sand would blow across the streets killing street dogs and waste burnt in the open,” he says.

The overlap between traffic and construction is an overlooked yet dangerous part of the build process. Harmful particles (PM₁₀ – the number defines the size of particle) are dropped along roads as lorries transport building waste.

Architect Rory Bergin of HTA Design says old construction trucks themselves are a major contributor to air pollution.

“The Ultra Low Emission Zones (ULEZs) should force firms to update their vehicles,” he adds. Surely ULEZs should therefore be rolled out across all UK cities.

Typically preoccupied with the promotion of their schemes as either ‘affordable’ or ‘luxury’, when they may be neither, developers are starting to shout about their green credentials.

Canary Wharf Group’s new 345-unit residential tower 10 Park Drive is the first construction site to support the mayor of London’s Clean Air campaign, badged a Considerate Constructors Scheme ultra site. Lorry drivers must turn idling engines off and ‘healthy’ building materials are being used, including water-based paint – the industry has moved away from oil-based, which gives off particles even when dry.

Old construction trucks themselves are a major contributor to air pollution. “The Ultra Low Emissions Zones should force firms to update their vehicles”

Materials are critical to low-carbon construction. The new buzzword is whole-life carbon, taking into account everything from the CO₂ from making the bricks and shipping them to site (embodied carbon) to the emissions from the building in use.

Tracing the environmental impact of every material is something architect Peter Clegg, partner at Feilden Clegg Bradley Studios, did 30 years ago, when designing Greenpeace’s headquarters. “That’s why we went with timber windows, even though at the time the slogan was ‘save a tree, use PVC’.

“Now we use a lot of PVC in our buildings. We need to find out about how our materials are sourced, what the recycling provision is and reduce usage.”

The architecture firm recently made its office canteen vegetarian and audited its rubbish to reduce its carbon footprint. The practice worked out that every vegan lunch offsets the office’s daily train and paper usage. But Clegg, who is on the steering committee of Architects’ Declare, a campaign that has seen more than 600 practices sign a pledge to pursue low-carbon architecture, knows the biggest impact the practice can have is through its buildings, by designing out things like concrete and steel.

Nick Searl, partner at developer Argent, agrees. He, alongside Clegg and hundreds of other built environment professionals, marched to Millbank for the Climate Strike on 20 September. “It’s clear that we need to be focusing on embodied carbon, not just operational,” says Searl. “I’ve heard that can account for up to 60% of a building’s carbon emissions.”

Searl believes the industry is waking up and willing to take action. “For the first time, we are on the cusp of real change. We’re having a lot more meaningful conversations.”

He adds: “What’s driving the change is this,” pointing at the thousands of adult and pupil protestors on the streets. “It’s public perception, from tenants to the wider movement, and most importantly perhaps, a new mood.”

Searl also says pension funds and larger investors are demanding greener buildings, which is driving change. “It’s not altruism. They see value in doing the right thing. There’s a fundamental shift to longer-term thinking.”

As for the Circular Economy, which would involve reusing materials in construction, such as bricks or aggregate, Searl believes it is “on the horizon”. He says: “I went to a big meeting at the [Greater London Authority] looking at how the Circular Economy can be built into policy.”

Cleaner building means manufacturing pre-fabricated homes off-site in factories

Bergin claims cleaner construction means manufacturing prefabricated homes offsite in factories. This halves activities on open sites, often in residential or built-up areas. “In a factory, everything is contained and dust is dealt with by vacuum machines,” he says.

Pre-fab off-site construction is still the exception, not the rule, in a sector that is under pressure to deliver homes fast but is also slow to change. “There is inertia in this conservative industry, the rationale being that a construction project failure is very expensive. Due to tight margins, developers also put very little investment into research and development,” says Bergin.

The use of timber creates a healthier working environment during its construction and makes the build process faster, thereby reducing environmental impact.

Green roofs and wild flowers are being planted to attract species and pollinators. Greening and rewilding of the urban scape is another way the developers can reduce air pollution – even if it is sometimes a planning condition rather than a proactive eco‑innovation.

At Westgate House in Brentford, 83 homes have been built right next to the M4 corridor. The challenge was to design a scheme that would reduce the toxicity of the air in and around the development. A 10-floor internal living wall, Europe’s biggest, helps to clean the air.

Architecture practice Assael worked with landscape architects Fabrik to design the living green wall, one of Europe’s largest at 10 storeys, in the atrium and a twin-skin glazed facade with a gap of 1.5 metres between the two layers.

“This acts as a natural chimney for the outside air to rise and helps control the internal temperature of the atrium,” says Assael’s Russell Pedley.

Air filters on the roof sift the air and cut NO_x levels by 40%. This air is then driven into the atrium, where it is cleaned again by the plants. The air is then finally pumped into homes.

All schemes by the developer HUB have mechanical ventilation and heat recovery systems, aka MVHR, which prevent heat leaking out into the atmosphere while allowing stale air to be extracted from the homes and fresher external air to be drawn in. They also take out any major air pollutants.

MVHR is becoming more commonplace in new builds but Bergin is sceptical. “These systems are getting more complicated and there is no proof they are being correctly installed – we don’t know what we’re doing is working,” he says.

What is the point anyway, if you step outside your air-filtered home into an air quality blackspot? Back in Lewisham, where Ella Kissi-Debrah died, planning was controversially granted for a residential scheme by Bluecroft Property Development right next to the A2. An air quality assessment showed the site contained 56.3µg of NO₂ per cubic metre where the legal maximum is 40µg. The strategic planning committee report requires the developer to advise residents to keep their windows closed and pay £7,500 towards monitoring air quality.

“Here’s the good news – we have the solutions to air pollution,” says Smedley. “Unlike climate change there is no 2º scenario, no knowledge that suggests things are going to get worse whatever we do. Urban air pollution is local, short-lived, and can be stopped at the source.”

Even more good news is the opportunity for developers to make a huge impact. According to Ben Smallwood from engineer Buro Happold, every 1% reduction in carbon emissions on the Temple Quarter project in Bristol is equivalent to 250 people going vegan for life. “You can make a huge difference,” he told an audience of architects at Feilden Clegg Bradley Studios.

An update from the London Atmospheric Emission Inventory earlier this year suggested NO_x levels are falling and could reach legal levels within six years.

Perhaps at this point there will be a stampede back into the capital in pursuit of Whitten’s urban idyll.

Designing and developing in response to environmental risk is a focus of The Developer Live: Risk & Resilience conference taking place on 8 November at Illuminate, Science Museum, in London. Register now. 

With reporting by Christine Murray from the Climate Strike