Forward-looking: Wooden houses are a fairly common sight in North American suburbs, thanks to the material's relative affordability in the continent. But they usually top out at just two or three stories. Now, thanks to a new technology called "mass timber" construction, wood can replicate the strength of steel beams and concrete – to a degree, at least.

A report by Knowable Magazine provides a rather insightful glimpse into the rise of mass timber and its benefits. The technique basically uses massive engineered wood elements instead of concrete and steel to build higher than ever before. As of 2024, mass timber buildings have climbed to almost unbelievable heights, with the 25-story Ascent tower in Milwaukee leading the pack.

The building is far from the only one in the category. The report states that there were 84 completed or under-construction mass timber buildings of eight stories or higher worldwide by 2022, with another 55 proposed. Europe dominates with 70% of these, but North America is catching up with around 20%.

As for what's driving this wooden renaissance, there are multiple reasons. For starters, mass timber could be an answer for reducing concrete and steel's massive carbon footprint, which alone makes up a whopping 15% of global emissions.

The magazine spoke to environmental scientist Diana Ürge-Vorsatz who highlighted mass timber's "double win" for emissions – both avoiding CO2 from manufacturing concrete and steel, while also locking away carbon stored in the wood itself. Her research estimated an 18-story building in British Columbia called Brock Commons saved over 2,400 tons of CO2 emissions this way.

Another proponent, a University of Toronto building scientist Ted Kesik, explained that "people actually enjoy looking at wood."

Taking a look at the "Mjøstårnet" in Norway, it's easy to imagine why. The building was certified as the world's tallest timber building at 85.4 meters (280 feet) at the time of its completion in 2019, though it's now lost the title to Milwaukee's Ascent. Both buildings are known for their warm, soothing interiors.

But what about issues like raw strength and fire resistance, which have historically held wooden buildings back? Well, mass timber uses elements like cross-laminated timber (CLT) panels that can match steel's strength pound-for-pound, thanks to layering and high-pressure gluing techniques.

Modern mass timber also passes rigorous fire testing. In the event of a fire, a protective char layer forms on the wood's surface, insulating the interior from flames long enough for evacuation and firefighter response.

Likely taking these perks into account, a 2021 update to the International Building Code gave mass timber a huge vote of confidence, allowing such constructions up to 18 stories in many places.

Of course, moisture poses risks that need careful management to prevent fungus and pests. But proponents are confident mass timber can be a sustainable solution if done right.

Image credit: Arch Daily, Think Wood

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Ikea-style wooden skyscrapers are popping up worldwide thanks to "mass timber"