Mass timber "positively not the appropriate approach to go" says Benjamin Kromoser

Mass timber is not going to turn into a mainstream constructing product as a result of it makes use of an excessive amount of wooden, development materials knowledgeable Benjamin Kromoser claims on this interview for the Timber Revolution.

“If we go extra within the route of mass-timber buildings we do not have sufficient materials, so the concept of scaling it up within the close to future will fail,” he informed Dezeen.

“I feel there will probably be a risk to scale it up a bit, so its use will go up within the subsequent few years – particularly in Sweden and Norway, the place they’ve constructed numerous cross-laminated timber manufacturing services.”

“However from my viewpoint, I feel we’ll attain the utmost of mass timber in at the very least 10 years. I feel, actually, will probably be earlier than 2030.”

“Utilizing wooden would not [automatically] make a constructing sustainable”

Kromoser leads the Institute of Inexperienced Civil Engineering on the College of Pure Sources and Life Sciences (BOKU) in Vienna, which receives funding from each business and public sector organisations.

He believes that the primary problem for the constructing business is utilizing fewer uncooked supplies total, relatively than merely switching from concrete and metal to biomaterials like wooden.

“Our purpose is to minimise the environmental affect of buildings over the entire lifecycle,” he mentioned.

“Utilizing wooden would not [automatically] make a constructing sustainable, as a result of mainly, what we have now as an issue is that in complete we want an excessive amount of supplies.”

Mass timber is the time period given to engineered wooden merchandise like cross-laminated timber (CLT) and glued laminated timber (glulam), which usually represent layers of wooden sure collectively to kind sturdy structural parts.

“Wooden is a restricted useful resource”

As a result of timber sequester carbon from the ambiance, changing closely polluting man-made supplies like concrete and metal for timber can considerably cut back the embodied carbon footprint of buildings.

However whereas mass timber can be utilized for taller buildings than typical timber-frame development, it makes use of way more wooden. That leads Kromoser to doubt its total sustainability.

“Wooden is a restricted useful resource,” he mentioned. “It at all times needs to be a steadiness between what we take from the forest to make use of for constructing development and the way a lot grows once more.”

“If we go within the route of constructing every part with CLT, then perhaps from the viewpoint of briefly storing CO2 it could be nice, however it’s positively not likely doable to scale that up.”

Catalyst building by Katerra
Mass timber often consists of layers of wooden sure collectively to kind sturdy structural parts. Picture courtesy of Katerra

Even in Austria, the place round half the nation is forested, he’s uncertain it could be doable to translate that into half of recent buildings in Vienna being constructed from mass timber.

As a substitute, he argues that to extend the proportion of development that makes use of wooden, extra material-efficient strategies like timber body should take priority.

“It could be nice if we might construct 50 per cent of the buildings in Vienna out of wooden however we’re far-off from that relating to the provision of the supplies, so going within the route of mass-timber development is fallacious,” he mentioned.

“We now have to go within the route of utilizing timber in probably the most environment friendly manner and which means structurally optimised buildings, so mass timber is unquestionably not the appropriate approach to go.”

“Timber framing is way more environment friendly, and you’ll quantify that with a life-cycle evaluation.”

Must “decouple” materials use from financial development

To supply one metre-cubed of CLT or glulam, round 2.5 metres cubed of wooden is required, roughly 25 per cent greater than for timber-frame development.

Kromoser argued that mass timber’s major utility needs to be for creating cantilevers or bearing heavy hundreds, or for dwelling areas in attic rooms because of its thermal massing properties.

“Timber is a superb materials, and mass timber the place it has its justification is an effective factor,” he mentioned. “However enthusiastic about how the constructing may be structurally optimised is a very essential factor to remember.”

“That is my key message, as a result of then we are able to cut back the quantity of uncooked materials required after which we are able to construct extra out of timber,” he continued.

He argues that depicting mass timber as a golden ticket to decarbonising the constructed atmosphere might threat distracting from the primary difficulty of fabric use.

“In the event you’re talking a few massive potential in mass timber development, it might justify for our society, ‘if we use this materials, it would not matter anymore how a lot we use’. That is completely not proper.”

The foremost problem, in line with Kromoser, is to lower the usage of uncooked supplies whereas nonetheless enabling the expansion of economies world wide.

“Additional improvement of society is at all times linked to a rise in supplies, and that is the fallacious route,” he mentioned.

“So what we actually have to consider is how we decouple the connection between materials use and the additional improvement of society. That is the most important difficulty and it isn’t linked to development materials.”

The highest photograph is courtesy of Benjamin Kromoser.

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Illustration by Yo Hosoyamada

Timber Revolution

This text is a part of Dezeen’s Timber Revolution sequence, which explores the potential of mass timber and asks whether or not going again to wooden as our main development materials can lead the world to a extra sustainable future.