Every day, fleets of heavy-duty dump trucks carry around 28,000 tons of construction waste out of London.
Much of the tangled steel rebar, hunks of concrete, and aluminium, stone, timber and glass from buildings demolished across the capital is destined for recycling plants, where it will be crushed into tiny fragments and turned into aggregate for use in building roads or foundations. A small percentage will be sent to landfill.
The carbon “embodied” in these materials — the emissions created in the sourcing and manufacturing of them — will be wasted.
A ruling due to come down next week will decide whether the daily exodus of construction debris from the capital will soon include the materials that make up Marks and Spencer’s flagship store near Marble Arch, at the western end of Oxford Street.
The retailer wants to demolish the Orchard House building, opened in 1930, and replace it and two neighbouring buildings with a 10-storey edifice comprising offices and a revamped store. Despite being granted planning permission by Westminster City Council in 2021, the scheme has become a lightning rod in a wider debate over the impact of the built environment on carbon emissions.
Opponents led by the conservation group SAVE Britain’s Heritage argue that demolishing it would be an affront not just to history but to the wider environment. Razing it to the ground would release 40,000 tonnes of embodied carbon, they say, the equivalent of almost 20,000 flights from London to Sydney — whereas a “retrofit” retaining parts of the building would leave a much smaller footprint.
The government decided the case was significant enough to review the council’s decision. In June 2022, the planning application was “called in” by the Leveling Up, Housing and Communities secretary Michael Gove. A planning inquiry into the proposal took place in London in November, and Gove is poised to issue a final decision by July 20.
The debate over the building has received national attention, catapulting the issues of embodied carbon and retrofitting from trade magazines into national newspapers. On one side, a range of conservationists, architects and engineers oppose what they say is an environmentally wasteful proposal whose approval would send a disastrous message about how seriously the UK takes its green commitments.
On the other, the retailer’s Oxford Street neighbours like Selfridges and Ikea support the company’s proposals as the best way to regenerate the city’s historic shopping destination, which in recent years has become increasingly down-at-heel.
Gove’s decision will go beyond the future of Oxford Street, however, and to the wider question of what role the construction industry plays in decarbonising the economy. The UK built environment is responsible for approximately 25 per cent of total UK greenhouse gas emissions, and the sector produces almost two-thirds of the waste Britain generates every year. If the UK is to meet its legally binding net zero commitments, it must make its building stock more sustainable.
The government recognises this to the extent that the energy consumption of buildings is now subject to rigorous standards. But emissions embodied in the construction process itself — the carbon cost of materials, maintenance and demolition — are not, either in building regulations or planning guidance.
Opponents of M&S’s Oxford Street scheme say this ruling is the government’s opportunity to set a precedent on what it expects from the owners and stewards of the country’s non-domestic buildings, of which there are 1.75mn in England and Wales alone.
Henrietta Billings, director of SAVE Britain’s Heritage, called it “a major test of our disposable, knock-it-down and rebuild attitude, [with] potentially far-reaching consequences for construction and development.”
The debate over M&S at Marble Arch is happening at a time when the construction industry is uniting behind a consensus of “retrofit first.” Industry trade publication The Architects Journal has led a campaign on the issue since 2019, while over the past year alone industry bodies from the UK Green Building Council to the London Property Alliance have published reports calling for government to set clearer standards. Although few will say so publicly, some feel the M&S inquiry is putting welcome pressure on government to catch up with where the industry says it already is.
“We’ve been doing construction in the same way for a long, long time,” says Kirsty Draper, head of sustainability at property advisers JLL, who co-authored the LPA report. “Now we’re realising we have to do things better.”
“The Arch”, a store that M&S’s venerated former chair Simon Marks once regularly patrolled to ensure standards were being upheld, might at first seem an unlikely vehicle for the hopes of the conservation lobby.
Despite a handsome art deco facade, it has little of the grandeur of its Beaux Arts neighbour Selfridges, and is not listed as having special architectural or historical significance. In M&S’s estimation, the overall quality of the three buildings that make up the site is “very poor”, according to Sacha Berendji, the retailer’s operations director. The buildings are old, poorly laid out and “riddled” with asbestos, he says.
M&S proposes to replace the store with a building it says will be among the most sustainable in London. It will be built along the principles of the “circular economy,” with 95 per cent of the existing materials recovered, recycled or reused in the new building. When completed, the company says it will use less than a quarter of the energy of the building it replaces.
These energy savings will eventually make up for the emissions from demolition and reconstruction, M&S says, delivering a so-called “carbon payback” within 11 years. The new building would have less retail space but more offices, creating jobs, regenerating the area and improving experiences for customers and local residents, says Berendji. “This scheme is good for the environment, for the economy, and it will be good for M&S.”
SAVE counters that a comprehensive retrofit of the existing building would do all that without the extraordinary upfront emissions of demolition. It also charges M&S with making “unreliable and unrealistic” accounts of the new scheme’s benefits, and estimates it would actually take three decades, if not longer, for the new building’s carbon savings to make up for those lost in demolition.
The proposal flies in the face not just of M&S’s own stated ambition to become carbon neutral by 2040, SAVE says, but also the UK government’s legal commitment to do so by 2050. Simon Sturgis, an architect and environmental consultant who acted as SAVE’s expert witness on embodied carbon, claims M&S refused to examine properly the case for refurbishment.
“They want to build a big new building because it’s going to be very valuable. That is the bottom line,” he says. “Whatever they say about the existing buildings, they are perfectly capable of being reused.”
Berendji rejects this. “Our position on all of our estate is always to start by asking the question: is refurbishment possible,” he says. “For Oxford Street, we looked at 16 different options, everything from a light to a deep refurbishment through to demolition.” But ultimately, he says, they concluded a refit is “not suitable, or viable” for a flagship retail experience.
“[M&S is] extremely well aware of the climate emergency and . . . are doing everything we can to minimise our carbon footprint,” he adds. “I would take massive issues with any suggestion that demolishing and rebuilding this isn’t actually better for the environment over the [life] of the building than worse.”
The retailer put these arguments to a planning inspector over the course of the 10-day hearing, while SAVE Britain’s Heritage made its own case with the aid of well-known advocates such as actor Kristin Scott-Thomas and comedian Griff Rhys-Jones. It made national and international headlines; a household name locked in a planning battle over the nation’s best-known shopping street. “It was emotive,” says architect Julia Barfield, who provided expert testimony against the scheme. “Everyone loves M&S.”
Berendji recognises the building sits on a faultline that runs through the construction and property industry. “There is a genuine debate to be had on refurbishment versus demolition, we are not dismissing that. But we just feel we have been on the right side of it every step of the way.”
He is concerned about the message it would send to businesses like M&S if Gove rules against the application. “I know that there’s a lot of others looking at this decision,” he says, who may base their investment decisions on “whether or not we get consent”.
Raze or remake
Every commercial building has obsolescence built into its fabric. Within a decade or two, its light fittings and ductwork will need extensive repairs or replacement. Its internal partitions, cladding materials and glazing will last perhaps 35 years.
With patchwork upgrades, a commercial building constructed today has a lifespan of between 60 and 100 years. For many buildings completed between the 1920s and the 1950s, their life cycle is coming to an end — presenting their owners with the same question faced by M&S: to raze, or remake?
“It’s a bit like buying a car isn’t it?” says Jason Millett, chief executive of consulting at construction group Mace. “Shall I buy the shiny new electric one, or stick with the one I’ve already got where all the carbon is already embedded? . . . It’s the same with buildings.”
In a report for Mace published in June entitled “Transform and Renew”, Millett made the case that the construction industry is better equipped and more willing than ever before to repurpose ageing commercial buildings to exceed contemporary energy efficiency standards. He says that provided buildings are well laid-out, with core elements like stairs and lift-shafts in the right places, “they can be refurbished”.
But the industry also understands it’s not a simple decision, says Draper of JLL. “When people talk about retrofit and demolition, they make it sound like a binary but it’s really not. The reality is that anything you do involves intervention, but the scale of that intervention sits across a huge spectrum.”
Buildings designed in the 1980s and 1990s “generally retrofit quite well”, she says. Their floors are laid out simply, they have good floor to ceiling heights, and lots of room for flexibility. But buildings from the postwar era, for example, present a “greater challenge”, says Draper, with common issues ranging from asbestos to inflexible floor layouts and poor structural integrity, limiting what can be done to revitalise them.
Developers are beginning to set their own benchmarks to dictate what approach they will take while also meeting their own net zero commitments. Grosvenor, whose core asset is the eponymous historic estate in central London, puts a cap on the amount of emissions that will be embodied in a building’s fabric on every new development.
“It provides a set of incentives and constraints,” says Ed Green, sustainability director of Grosvenor Property UK. “Designers and developers are great problem-solvers and respond very well to constraints.” He says that since they introduced the cap, which will be lowered over coming years, the company has not demolished a single building.
The challenge for the industry, says Green, is that national planning policy and building standards do not state what level of embodied emissions is acceptable, nor give a unified definition of what they are for different materials and processes.
This puts the UK behind other countries such as Sweden, Denmark, France, Finland and the Netherlands, which now regulate “whole-of-life” carbon emissions. Some planning authorities in Britain now require whole-life carbon assessments to be carried out, but without set benchmarks or targets.
With a regulatory focus solely on a building’s operational emissions, says Green, you risk skewing incentives for developers. “Let’s say it’s 2015. You could build the world’s most sustainable building, then 10 years later decide to knock it down and build what in 2025 would be the world’s most sustainable building — and still sell that as a really sustainable thing to do.”
The issue will only become more acute as buildings become more operationally efficient and embodied carbon accounts for a greater share of the total carbon cost.
Seeking clarity, the construction industry’s main professional groups united in July 2021 to propose an amendment to the building regulations entitled “Plan Z”. For the first time, it would set requirements on how to assess a building’s whole-life carbon footprint and limit embodied emissions for all major building projects.
Conservative MP Jerome Mayhew has put forward a bill in the House of Commons that would put the proposals into law but it has not yet been taken up by government after a second reading in November.
“The government decided two things: one, we don’t think there is industry consensus on this. And two, there’s a risk to SMEs,” says Will Hurst, managing editor of The Architects Journal, who has spearheaded its RetroFirst campaign. It’s frustrating, he says, because “there is a clear direction of travel, and growing calls for action . . . there is cross-industry consensus on this.”
In the absence of any indication of how important embodied carbon is to government, says Hurst, “people are hoping the M&S decision fills that vacuum”.
In making that decision, Gove must take into account the findings of the planning inspector, David Nicholson, who has past form with embodied carbon; it was one of the reasons he recommended rejecting the “Tulip,” an observation tower designed by Lord Norman Foster in the City of London.
In the meantime, Sturgis believes the public furore over M&S is making other developers think twice. The City of London Corporation announced proposals last year to demolish Bastion House, a modernist office block near the Barbican estate, as well as the neighbouring Museum of London, to make way for an ambitious new development. Like M&S, it said the existing buildings were “unsustainable, outdated” and beyond saving.
But after an outcry from locals, media, and heritage groups, the corporation backtracked to look again at whether it is possible to retain the buildings. After conducting a “soft market testing exercise”, it says it has “several expressions of interest which we are currently reviewing . . . we are keeping all options for this site”.
“The message is starting to filter through,” says Sturgis. He points to the redevelopment of Euston Tower, the 1970 skyscraper whose developer has said it will aim to reuse at least a quarter of the existing building’s fabric. “British Land is working hard to figure out how much of it they can keep. Ten years ago, they would have just knocked it [all] down.”