From materials innovation to modular construction: The property sector plots its pathway to net zero

As the government prepares to kickstart the economy by loosening planning regulations in the hope of spurring a boom in infrastructure and construction projects, the need to curb the carbon emissions associated with buildings remains as pressing as ever.

Developers across the country are facing growing pressure from shareholders, campaigners, and customers to advance a greener, cleaner built environment as construction sites attempt to get back on track post-lockdown, with campaigners warning the government's 'build, build, build' agenda and its plans for a controversial overhaul of planning regulations to speed up the UK's development pipeline could further exacerbate the climate emergency if green safeguards are not put in place.

While industry pledges and building standards have been largely centred around efforts to reduce operational emissions - the carbon incurred by energy used to heat, cool, and light buildings - there has also been growing scrutiny ahead of the anticipated construction bonanza on the other major sources of emissions associated with buildings, namely the emissions associated with construction activity and the materials used in buildings. Zero emissions equipment, modular construction methods, and materials innovation have all been touted as avenues the industry must explore to drive down these emissions in line with the UK's national net zero emissions goal.

Thankfully, a raft of new climate commitments and projects announced this summer by major developers suggests much of the sector remains committed to the net zero agenda despite the expected economic downturn and the pandemic's chilling effect on development pipelines.

For example, British Land - one of the UK's most prolific commercial property developers - has pledged to achieve net zero emissions across its portfolio by 2030 for both operational and embodied carbon. The firm plans  to slash its absolute embodied carbon emissions in half by 2030 against a new 2019 baseline and operational emissions by 75 per cent with any remaining emissions set to be offset.

Simon Carter, chief financial officer of British Land, explained to BusinessGreen that the firm's embodied carbon reduction vision would require a combination of the strategic use of existing structures when redeveloping sites and significant materials innovation. "There are some materials available today that have lower carbon, special forms of concrete for example, steel that has lower carbon, and those are obvious avenues to explore," he said. "But we'll have to go beyond that."

A zero carbon future will rely as much on embracing new types of building materials as rethinking old ones, he explained, and the firm is currently exploring the use cross-laminated timber (CLT), a robust wood panel product prefabricated from gluing several layers of wood together. But to drive its acceptance, work needs to be done to break down preconceptions that timber is flammable and therefore a dangerous material to build with. "Early studies suggest that CLT has the same combustion point of steel, so actually it shouldn't be any different," he explained.

Carter emphasised that developing solutions that fulfil customers' appetite for greener buildings would require collaboration across the supply chain, and that a healthy appetite from customers should serve as a catalyst for these partnerships. "We're seeing our customers becoming very focused on this area - which is great, because when the customer wants something it tends to lead to change and innovation," he said.

There are signs across various materials sectors that innovation is indeed underway. Recently 40 of the world's leading cement and concrete companies unveiled a collective ambition to steer the industry towards a carbon neutral future through measures to reduce and eliminate energy-related emissions, deploy carbon capture, and promote the reuse and recycling of concrete. Meanwhile, in Sweden, the world's first hydrogen-powered steel plant was powered up on 31 August by the HYBRIT coalition.

Carter reflected that the appetite for green buildings and construction materials does not seem to have been dimmed in the wake of the pandemic squeeze on construction schedules, noting that there was a real "commercial advantage" to developing sustainable buildings. In the wake of the crisis, he said, stakeholders are more concerned about sustainability than ever before, and the businesses that comprise the large proportion of British Land's customer base - media companies, financial services providers, and technology firms - remain focused on reducing the operational emissions of their offices."Sustainability at the end of the day is about making the business sustain into the future, and this crisis is reinforcing the view that things can happen unexpectedly and you need to protect against those items," he added. "I'm hopeful that going forward the crisis will maybe engender a real culture of innovation."

A number of project updates announced this summer provide further proof of developers growing green ambitions. For example, Landsec announced it had started planning the UK's first net zero commercial development in Southwark, London using a "platform-led" design kit approach, while a 60-storey building in Bishopsgate, London delivered by WSP sped past its embodied carbon reduction expectations by reusing existing foundations, deploying lightweight concrete, avoiding 'over-designs', minimising waste, and opting for a 'top down construction approach' that reduced construction time by three months.

Meanwhile, property investor and housebuilder Legal & General is another firm that boosted its sustainability ambitions this summer. In late June, the firm committed to making all its carbon stock operational net zero carbon by 2030, while taking steps to "understand, monitor and reduce" its embodied emissions. In addition, it reaffirmed its commitment to build 3,000 modular homes by 2024 at its 550,000 square foot facility in Yorkshire.

Advocates of factory built housing maintain it can reduce construction costs and timelines, slash the emissions generated by the transportation of materials, and integrate more easily with grid connections, delivering major sustainability gains.

"Modular brings all sorts of opportunities to be efficient and to be much more tuned in to consuming as little energy as possible and conserving resources," explained L&G's head of real assets Bill Hughes. Legal & General's modular product portfolio has smaller embodied carbon emissions than traditionally-built homes and are built to EPC standard A, the gold standard of energy efficiency enjoyed by less than one per cent of dwellings in England and Wales.

Hughes predicted that modular homes will take up a growing share of the UK's new built housing market as customers seek to benefit from the lower embodied and operational emissions of factory built housing. "Traditional will remain, but there will be a higher percentage of modular than there has been in the past," he said.

As such he called on the government for a stronger policy framework to catalyse the net zero building revolution, noting that a "carrots-and-sticks" approach is now needed to catalyse the sector. This could include incentives, such as time-limited subsidies and the introduction of official thresholds that penalise bad energy performance, he said. "We need to see more government engagement in terms of putting in a framework," he said. "If the viability of moving to net zero is highly challenged, it becomes harder to do it."

While stressing that L&G's net zero agenda has not been diluted by the pandemic, Hughes reflected that the net zero agenda risked being  temporarily shelved at organisations that might be "fighting for survival" in the wake of the pandemic.

Overall, however, Hughes noted that there had been a "sea change" when it comes to the acknowledgement and recognition from society and investors of the importance of sustainability in the property sector. Whereas 12 years ago, sustainability was an issue that was "bordering on quirky", he said that it was now a "top three issue, pivotal and essential".

Leading businesses across the construction sector have made it clear they want to accelerate the adoption of greener building practices. With the government yet to finalise its promised Future Homes Standard and wide-ranging planning reforms, it is to be hoped Ministers take steps to further drive the trend for greener homes and offices and do not inadvertently usher in a new wave of unsustainable developments.

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