Is Bamboo the Building Material of the Future?
The Food and Agriculture Organization of the United Nations estimates that between 2015 and 2020, the planet lost 10 million hectares of forest a year to deforestation. While this paints a dire picture for biodiversity, Indigenous sovereignty, and a rapidly changing climate, there is hope on the horizon. A growing industry of sustainable building materials promises to curb deforestation and sequester a significant amount of carbon in the process.
Chief among them is bamboo. While traditional hardwood lumber can require 70 years to reach maturity, species of bamboo can be harvested in five to seven years. By far the fastest-growing woody plant on Earth, bamboo is actually a grass with a wide variety of applications from musical instruments to toilet paper and even wind turbines.
Beyond its ability to regenerate quickly, bamboo offers a multitude of benefits. It thrives in poor soil conditions, prevents erosion, and requires minimal inputs such as fertilizer and pesticide, cutting down on water pollution. Even better, bamboo’s tensile strength per weight unit is greater than steel.
According to David Sands, co-founder of bamboo timber company Rizome, if bamboo made up even a modest market share of building materials, the climate impact could be monumental.
“Right now the projection is that the square footage of buildings on the planet is going to double in the next 40 years, and if that’s business as usual, that’s really going to sink our boat in terms of climate impact,” he says. “If we can replace wood, concrete, and steel [with bamboo], at 12 per cent of global construction that would address one-third of humanity’s entire output of CO2.”
This figure includes bamboo’s actual carbon drawdown as well as the emissions avoided from steel and concrete production and cutting down trees for lumber. To convert this ambitious projection into a reality, Rizome is working to establish a large-scale global supply chain and provide engineered bamboo timber for a burgeoning market.
Sands’ epiphany came when he was building an off-grid home on Maui in the 1990s. Despite his attempts to use recycled materials, he realized that “there’s a whole forest that goes into every house in the U.S.”
Now Rizome is partnering with indigenous groups in Mindanao, the southernmost island in the Philippines. Decades of deforestation altered microclimates across Mindanao, making it more susceptible to wildfires and preventing reforestation efforts. “The only thing that was surviving the fires was the bamboo,” Sands says. “Now we’re under contract to plant tens of thousands of acres over the next few years.”
With a large planting operation underway and a new processing facility recently completed, Rizome is poised to feed a growing market across Asia. But this highlights one of the most common critiques of bamboo: about 80 per cent of the world’s bamboo forest area is in Southeast Asia. The necessity of transcontinental ocean freight contributes to greater emissions, reducing bamboo’s efficiency as a carbon sink (though it still has lower lifetime emissions than traditional timber).
To address this issue, Rizome is starting operations in Florida, with impressive results. “We did some test plots that exceeded anybody’s expectations,” Sands says. “At 14 or 15 months, we had 30-foot-tall plants with 50 culms.” Each of these culms could produce a 220-pound pole, which can be harvested and processed into lumber.
As global demand increases, bamboo might move from a fringe building material to a commonplace component in homes and businesses around the world. While it seems far-fetched, some architects even hope to build skyscrapers using bamboo as a key material. Perhaps, if the bamboo industry grows as persistently as its primary product, an idealistic world with healthy forests, a stable climate, and regenerative building materials is more than a utopian fantasy.