Does wood hold the key to construction sustainability?
It's strong, versatile and literally as old as the hills so it's perhaps hardly surprising that wood is experiencing a renaissance in a net-zero world where developers are looking to reduce their cement inventory.
From schools to corporate headquarters and even football clubs, organisations are looking at how best to cut carbon emissions globally, and that's sent demand for wood, and prices, rocketing.
Nick Boulton, Head of Technical and Trade at the Timber Trade Federation, said demand for timber products and many other building materials continues to outstrip available supply, creating a risk that demand-led inflation may choke off the sector's projected pace of recovery.
“We are seeing demand for wood products continuing to increase at UK, EU and Global levels which coupled with ongoing supply chain disruptions caused by Covid restrictions has inflated prices and extended lead times," he said.
But soaring prices are not denting ambitions. When complete, Ascent in Milwaukee’s East Town neighbourhood will be the tallest timber structure in the world (main photo). The 493,000-square-foot, mixed-use building will contain 259 apartments, a pool on the sixth floor, and a top floor amenity level.
The Wood CO2ts less campaign encourages using more wood to reduce CO2 emissions and highlights a number of low-carbon case studies. Flexibility is an important attribute; 6 Orsman Road, for example, has been designed to adapt and evolve as required. "The use of a prefabricated CLT-steel frame creates large column-free spaces that enable flexible configuration of internal layouts to suit changing tenant needs," it notes.
Last Thursday, industry experts gathered to discuss how wood can successfully be used as a building material to create sustainable learning environments. Hosted by Stora Enso, in collaboration with The B1M, the webinar showcased the award-winning case study of the Northstowe Learning Community in Cambridgeshire, UK, a 15, 000sqm project that utilised Cross Laminated Timber (CLT) to meet sustainability targets and provide an inspiring and healthy space for students.
Rory Doak, Business Development Manager UK & Ireland at Stora Enso, said: “The biggest impact [of the Northstowe project] is that there’s nearly 3,000 tons of CO2 stored in the building that’s not getting put back into the atmosphere”. Pair this with the reduction of up to 75% of CO2 emissions that can be achieved using wooden construction methods versus concrete and steel processes, and it’s clear to see how building with wood can contribute to this journey.
Also touching on the biophilic design nature of wood, the panellists shared insights on its positive impact on the health and well-being of children as studies have shown that the material can improve concentration and reduce stress. With return to classrooms post-pandemic in motion, this will be an incredibly important factor for educational authorities and construction players to consider.
But the webinar also assessed the barriers to adopting CLT as a construction material, from concerns around technical performance, to miseducation on cost-effectiveness.
Dayo ShittuBalogun, Associate at EURBAN, said: “We’re coming across a lot of risk aversion as people still consider wood construction as a new way of doing things. There is some miseducation on cost. People consider it to be a bit more expensive, but through some benchmarking work we established that if you’re talking in simplistic terms, the structural skeleton of a building is either equal or cheaper – and more work needs to be done to communicate that this is the case.”
When looking at the path forward for sustainable school construction in light of the Northstowe project, ShittuBalogun, added, “We all have a commitment to not pour more CO2 into the atmosphere than we take out of it, so there is a moral obligation for all of us across the industry – and where better to see this play out than in an educational setting? This is exactly what we like to do, deliver buildings efficiently and sustainably.”
Fred Mills, Co-Founder of The B1M, and webinar moderator, said construction methods have the power to truly effect people’s lives. "It perhaps doesn’t get more important than thinking about this in the context of where future generations are learning. Wooden school projects create amazing spaces for schooling, both from an environmental, health and well-being point of view. The task now, is to raise awareness of how concepts can be moved to an implementable reality and Northstowe is a fantastic example of this.”
Five years after introducing see-through wood building material, researchers in Sweden have taken it to another level. They have found a way to make their composite 100 percent renewable – and more translucent – by infusing wood with a clear bio-plastic made from citrus fruit (click here). “The new limonene acrylate it is made from renewable citrus, such as peel waste that can be recycled from the orange juice industry,” says lead author, PhD student Céline Montanari.
Forest Green Rovers' new Eco Park stadium - given the green light last August - will be made from mass timber, a catch-all term for engineered wood that’s cut into slabs and then stacked together to make strong panels or beams, with designs provided by world-renowned architectural practice Zaha Hadid.
In every sphere, wood's appeal appears to be on ever-firmer foundations.
ReCreate project reuses concrete in new buildings
Reconciling the carbon conundrum in construction will not be a quick fix but researchers at Finland's Tampere University may have hit on a way of deconstructing concrete elements and reusing them in new buildings.
Its four-year ReCreate project, which has received €12.5 million of funding under the EU’s Horizon 2020 programme, involves universities and regional company clusters in Finland, Sweden, the Netherlands, and Germany. All the country clusters will carry out their own pilot projects where they deconstruct precast concrete elements intact and reuse them in a new building.
“By reusing concrete elements, we can save an enormous amount of energy and raw materials,” says Satu Huuhka, adjunct professor at the Faculty of Built Environment at Tampere University, who leads the ReCreate project. “We are specifically looking to reuse the concrete elements as a whole, not as a raw material for something new."
Researchers at the Faculty of Built Environment have been carrying out ground-breaking research into the circular economy in the construction sector for a decade.
Long-term research on renovation and the lifecycle engineering of structures provides a solid foundation for the development of quality assurance procedures that will ensure the safety and integrity of the reused elements. This time, the researchers are set to explore not only the technical implementation of the solutions but also the business perspective.
Huuhka acknowledges there are many unanswerered questions, from assessing structural integrity to building code requirements - and ultimately how to turn ReCreate into a viable business. "We must also consider the social aspects: does the process require new skills or new ways of working?” he adds.
Tampere University researchers will also bring to the project their specialist expertise in circular economy business models, building regulations and law, and occupational sociology. The Finnish country cluster comprises Tampere University, Skanska, demolition company Umacon, precast concrete company Consolis Parma, engineering and consultancy company Ramboll, architecture firm Liike Oy Arkkitehtistudio and the City of Tampere. The communications partner is the Croatia Green Building Council.
Buildings generate nearly 40% of GHG emissions and the rising pace of construction - up to 2 trillion square feet could be added by 2060 - means finding a sustainable concrete solution is essential.
Graphene concrete on firm foundations, CarbonCure accelerates growth and Nexii expands in US
Nationwide Engineering is claiming a world first today as it lays the world's first graphene concrete slab engineered for sustainability in a commercial setting. The new material is strengthened by around 30% compared to standard concrete and so significantly cutting material use.
It has partnered with the University of Manchester's Graphene Engineering Innovation Centre and structural engineers HBPW Consulting; graphene is an allotrope of carbon and the resulting mix with concrete produces a substance that area for area, is stronger than steel, it claims.
CarbonCure manufactures a technology for the concrete industry that introduces recycled CO₂ into fresh concrete to reduce its carbon footprint without compromising performance. It was named one of two winners in the US$20 million NRG COSIA Carbon XPRIZE and the money will be used to accelerate its mission of reducing 500 million tonnes of carbon emissions annually by 2030. Carbon Cure believes the use of CO2 in concrete is expected to become a US$400 billion market opportunity.
Nexii designs and manufactures high-performance buildings and green building products that are sustainable, cost-efficient and resilient in the face of climate change. It recently teamed up with actor and Pittsburgh native Michael Keaton, who will have an ownership stake and play an active role in Nexii’s upcoming manufacturing plant, which will be its second in the United States and sixth overall.