Jonathan Morrison
Best eco building designs: from wooden towers to green stadiums
With the UK committed to becoming ‘carbon net zero’ by 2050, Jonathan Morrison looks at the environmentally friendly design tricks that will help to get us there
Build back better” - that was the exhortation from the prime minister last summer and, while Boris Johnson’s choice of pet infrastructure projects can lead to elevated eyebrows at times (bridge to France or tunnel to Ireland, anyone?), there’s no disputing that the architecture and construction industries have work to do if we are to emerge from the pandemic into a greener new world.
If the coronavirus is hopefully, finally, on its way out, the threat of global warming is not. So in an attempt to tackle this, or at least shame others into taking action, the government has committed to the UK becoming “carbon net zero” by 2050 (meaning that any unavoidable emissions are offset). But we remain some way off that target and buildings, unfortunately, are a key reason for this.
Globally the construction industry accounts for 38 per cent of CO2 emissions, according to a report by the United Nations Environment Programme based on 2019, the last year before the pandemic struck. The four billion tonnes of cement production a year account for 8 per cent — only coal, oil and gas are bigger sources of greenhouse gases. About 45 per cent of UK emissions come from the built environment, with about 10 per cent directly associated with construction (according to the UK Green Building Council). So there will need to be a sea change if we are to prevent a real sea change drowning everything south of the Highlands. How can this be achieved?
Use more wood
“Nothing else comes close to timber,” says Andrew Waugh, of the Waugh Thistleton, one of the leading sustainable design practices. “We’ll never get to zero carbon using concrete and steel. We’re facing a once-in-a-species event and timber is the only true carbon sink. I can’t see an alternative.”
Trees, which are about 70 per cent carbon, capture CO2 from the atmosphere and transform it into biomass through photosynthesis. That carbon is still locked away if the tree is used for construction and any replacement trees sequester more.
For this reason France, which has pledged to be net carbon neutral by 2050, has announced that from 2022 all new public buildings will have to be at least 50 per cent timber. And for added emphasis, any building in the 2024 Paris Olympic complex above eight storeys will have to be built entirely from timber.
Forest Green Rovers’ eco stadium, by Zaha Hadid Architects (NEGATIV)
There is no reason timber can’t be used for most types of buildings. Cross-laminated timber (CLT), which is made from planks of pine or spruce glued at right angles, is enormously strong as well as fire-resistant. A CLT skyscraper reaching 85.4m in height and 18 storeys was completed in Brumunddal, Norway, in 2019; another of 21 storeys is rising in Amsterdam. A mostly CLT office complex alongside a railway line on Old Paradise Street in Vauxhall, London, by Feilden Clegg Bradley, will sequester enough carbon to compensate for the first 60 years of its operation. And work is under way on the world’s first football stadium to be constructed almost entirely from timber, designed by Zaha Hadid Architects for Forest Green Rovers, the League Two club based in Gloucestershire. It will have the lowest carbon footprint of any stadium in the world once complete.
Choose from a smorgasbord of new materials
There are plenty of other materials that have properly green credentials. Hemp can be woven into insulation panels, thatch has been used to wrap alpine huts, and straw bales and sandbags form the walls of an unusual house just north of King’s Cross in London, by Sarah Wigglesworth, which featured in an early episode of Grand Designs. Waugh Thistleton even won awards by using rammed earth walls — more common in the Middle East and Africa perhaps — at the beautiful Bushey Jewish Cemetery in Hertfordshire, which is both genuinely spiritual and designed to to fold seamlessly back into the countryside after a lifespan of about 80 years.
Bushey Jewish Cemetery, Hertfordshire (LEWIS KHAN)
There are many recycled products on the market too: enzyme-bonded sheets of cardboard, paper waste or even potato peelings (called, inevitably, Chip[s] Board). There’s ferrock, which uses steel dust, and timbercrete, made of concrete and sawdust. There are recycled plastic tiles and there are even houses made entirely from reclaimed bricks.
Look locally
Perhaps you don’t want to use recycled PVC shingles and favour something more in keeping with the vernacular. Proving that traditional architecture can be eco-friendly, Robert Adam, perhaps the foremost exponent of classical styles, is in the process of creating a a multimillion pound country pile in Sussex that aspires to be zero-carbon, but which wouldn’t look out of place as a backdrop for Bridgerton. The majority of the components are to be sourced from within a scone’s throw of a petulant Regency dandy, rather than trucked from afar (which is up to 15 per cent of the carbon footprint). Lumber will be taken from the estate’s woods, bricks and roof tiles dug from clay deposits and fired with more wood, and lime for the mortar comes from a nearby chalk pit. To save further on carbon, the house has been built off solid ground, as in days gone by, without extensive concrete foundations. Hemp for insulation is grow nearby and photovoltaic panels are hidden in a field.
“It contradicts the established view that if it’s going to be sustainable, it has to be wonky,” Adam says. “The only drawback is that everything takes longer — you have to cure the timber for a year, for example — but it can work out cheaper.”
Bio-mimicry
Going back to nature isn’t only important when it comes to picking materials, it provides a model for how you use them. For example, as 3D printing becomes more common, a lot of thought has been put into getting the maximum benefit from the minimum amount of matter, but nowhere is this more important than on another planet where the cost of transporting cargo is quite literally astronomical. So as part of the Nasa competition to design a Martian base, Foster + Partners, the UK’s largest firm of architects, proposed using 3D-printing robots to replicate the bone structures of avian wings, which are lightweight and exceedingly strong. The bones of Owl wings, incidentally, are being used as a model for a new generation of turbine blades in jet engines for that very reason.
Another example is the Sahara Forest Project in Qatar, a solar-powered and seawater-cooled greenhouse is modelled on the Namibian fog-basking beetle, an insect that harvests its own fresh water using the texture of its bumpy abdomen. In the greenhouse water vapour is captured by grilles on the roof and channelled to soil beds below, potentially offering a mechanism to expand agriculture into arid regions.
A cross-laminated timber skyscraper in Brumunddal, Norway (OYSTEIN ELGSAAS/VOLL ARKITEKTER)
Greenery
There have been numerous experiments with covering buildings with greenery, but few are as dramatic as the Bosco Verticale in Milan, which opened in 2014 and has large planters on the outside of its two towers. The 21,000 items of flora were carefully picked: the 800 trees are deciduous and provide shade in summer while letting light through in winter. It may require the attention of “flying gardeners” twice a year, and thousands of ladybirds to keep the aphid population down, but the project, by Stefano Boeri, has been declared a success. Boeri, who describes the COIMA-owned Bosco Verticale as “a lab, a prototype and a benchmark”, is now working on new tree-covered suburbs in Milan, Liuzhou in China, and a “smart city” for 100,000 near Cancún, Mexico. All will feature extensive parkland and be largely car-free.
The global engineering group Arup has been looking at the subject of “green walls” and evaluating how effective they are. It has come to an astounding conclusion: covering 20 per cent of 20 per cent of buildings in inner cities (just the roof of a fifth of the buildings) could reduce temperature peaks on Hong Kong Island or in central Melbourne by as much as 10C, 3-4C in Berlin, or 2C in London or Los Angeles. If it were done worldwide, we would be zero carbon by 2050. “Every plant counts,” as Rudi Scheuermann, a director of Arup, puts it. “Rather than build a few zero-carbon structures, we need to tackle all the existing building fabric. Greening cities would be a big step forward but affordable; we just need to give nature a hand.”
Self-sufficiency
How do you water all that greenery, though? The best new buildings are rapidly becoming self-sufficient when it comes to rainwater harvesting, reusing “grey” or waste water — even if it’s only to flush toilets — and in electricity generation too. Technology keeps on giving: with photovoltaic panels, built-in wind turbines, ground-source heat pumps and even thermobimetal shutters, made from metal alloys that expand and close in the heat, there’s no reason why buildings need to be such a continual drain on the grid. Using an expensive office block for a mere eight to ten hours a day is starting to look pretty profligate too.
Of course, simple things like good insulation also make one heck of a difference.
Longevity
Flexibility is ever more important as we look to get the most from the buildings we already have, but flexibility also increases a building’s lifespan — look at all the Georgian townhouses in Mayfair that are still going strong as hedge-fund headquarters.
“Longevity is the elephant in the room when it comes to sustainability,” Adam says. “The most eco-friendly building is the one that is already there, that’s 300 years old and hasn’t had to be rebuilt four times.”
The Landscape Park Duisburg-Nord, Germany (TOURISMUS NRW EV)
Hang on, you might say — posh London terraces might be easy to adapt, but what about everything else? Almost anything can be given a fresh lease of life with sufficient imagination. One of the most extraordinary tourist attractions in Germany is an old steelworks — the Landscape Park Duisburg-Nord — in the heart of the Ruhr. A less promising starting point would be hard to find than this dystopian landscape of rusting towers, blast furnaces, storage bunkers, sewers and railway tracks that was finally abandoned in 1989. Yet since then something akin to alchemy has been performed. An old gasometer has become Europe’s largest artificial diving centre. There’s an alpine climbing centre and a high-ropes course in a casthouse. There are light shows, theatre productions and films (shown and shot). Polluted soils are redeemed through greenery, memories shared in new piazzas, young minds inspired. Before the pandemic, there were nearly a million visitors a year to this utterly alien but mesmerising place, which is unlike anywhere you will have been before. So who’s to say what can’t be achieved with imagination?
Where there is a will
Imagination and will, that is. You may not recall Friday September 20, 2019, but it was a day unlike any other in architecture: for the first time studios across the country shut down and staff walked out in a coordinated protest over climate change. Did anyone notice? Probably not. The work would get done anyway, the building sites were thronged. And herein lies the problem: without someone at the top table taking notice, none of it matters. Architects and engineers can come up with solutions but, if the political will is lacking, it’s pointless. As David Attenborough put it: “We’re refusing to take steps that we know have to be taken.” But it’s not just a British problem. The UK is only 1 per cent of global emissions.
So much is riding on the UN Climate Change Conference in Glasgow in November. About 200 world leaders will attend, including a more sympathetic US president than before. Will it be enough to shake an apathetic world? Will any profound commitment emerge or binding target? Can it add to the Paris agreements five years before or will it be so much bluster and braying? I’m afraid it’s back to you, Boris...
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