These Taiwanese Companies Are Turning Waste Into Building Materials

Insect shells, rice husks, water bottles, and bamboo charcoal might not be the first things that come to mind when you think of high-^­performance building products. But Taiwanese upcycling company Miniwiz is using them to create just that. “We take leftover construction waste, leftover fiber waste, leftover plastic or packaging waste, and turn that into a building material you can use for another 30 years,” says CEO Arthur Huang.

Carbon emissions from the built environment include “operational” carbon generated through uses like lighting and ventilation, and “embodied” or “embedded” carbon, created during the process of material extraction, manufacturing, and transportation. Embedded carbon is expected to contribute to nearly half of new construction emissions between 2020 and 2050.

“We solve the embedded-carbon footprint issue by very dumb logic,” Huang says. “You just use the carbon you’ve already produced.”

Read More: How the Cement Industry Is Creating Carbon-Negative Building Materials

Mining and extraction of materials for the modern construction industry is carbon-­intensive, but Huang believes we can eliminate the carbon released by new material production by using things we would otherwise throw away.

Miniwiz has invented processes to turn over 1,200 kinds of local waste into building products that can function as everything from brick or wall panels to tiles and air filters; since its inception in 2005, Miniwiz has built a number of large-scale structures including the earthquake- and fire-resistant Taipei EcoARK, composed of over 1.5 million PET bottles, and Anything Butts, a modular structure made from recycled cigarette butts. Recent projects like the wall fabric in Hong Kong’s AIRSIDE shopping mall built in 2023 reduce carbon emissions by over 70% compared with traditional materials, according to Miniwiz’s CO₂ Emissions Summary.

Concrete, one of the most commonly used traditional construction materials, contributes up to 8% of total annual emissions. Wen-yi Kuo, founder of material-­development company LOTOS, works on reducing emissions by extending the life of concrete, and ultimately hopes to replace the material with local waste-based alternatives.

Kuo has developed a product to help tackle the toll humidity can take on buildings in Taiwan. The natural stucco, made from waste silt dredged from Taiwan’s water reservoirs, can replace cement-based alternatives. The material prevents water damage to concrete buildings and can be added to cement mortar as a waterproofing agent.

He went on to co-create C-Slurry, a concrete substitute that uses industrial waste like blast-furnace slag from steel­making instead of cement as a binder, combining it with other forms of local waste like oyster shells and demolished red brick to invent alternative low-carbon building materials. 

“If we want to be lower-carbon and circular, most of the materials need to be local,” says Kuo. “This has the added benefit of reducing carbon emissions from shipping and transportation.”

Persuading customers to try something new in Taiwan’s “conservative” construction industry is a challenge, Kuo says.“We introduce the new technology to help solve people’s problems, and build trust from there.”

“In the end it comes down to whether someone has the consciousness and they’re willing to pay for this,” Miniwiz’s Huang adds. “So we are using technology to find a way to produce at half the price, twice as good.”