Homes made from grass? NC startup inks major deal with the largest US builder to do it.

Within a former tobacco factory in the Granville County town of Oxford, Huade Tan and Nathan Silvernail believe they can upend how houses get built.

While plenty of businesses supply home panels sourced from trees, their startup Plantd harvests a 20-foot-tall perennial grass — the exact type its founders declined to divulge. The company then disassembles this hard grass into high-strength fibers, dries it, blends it, rolls it out and finally cuts it into four-by-eight-foot sheets.

Earlier this month, Plantd signed an agreement with the nation’s largest construction firm, D.R. Horton, to provide 10 million panels ,roughly enough to build 90,000 homes. It is by far the largest order to date for the 3-year-old company.

“It doesn’t change the way you live,” Silvernail said, referencing the light-brown panels that look and feel like tree-made wood.

The advantage of grass, the CEOs say, is its speed. The most popular tree for producing lumber in North Carolina is loblolly pine, which loggers grow for around 15 years before cutting. Grass only takes a few years to mature and then can be harvested in North Carolina’s temperature climate once or even twice annually.

“We don’t think you can do business as usual and just continue the cycle,” Tan said. “Like we’re rethinking the entire supply chain of an entire industry.”

Silvernail and Tan met in California as coworkers at Elon Musk’s aeronautics company SpaceX. “We were miserable,” Silvernail acknowledged.

During coffee breaks, they would discuss carbon sequestration, the process of pulling carbon dioxide gas from the atmosphere and storing it as a liquid or solid. The two wished to turn CO2 into something useful, and housing materials seemed to have a clear societal benefit. Tan left SpaceX first and relocated with his family to the North Carolina Triangle. Silvernail followed a few years later.

Tan and Silvernail incorporated Plantd in May 2021, along with a third cofounder, Josh Dorfman. They established a facility in Durham and spent their first year identifying the best alternative building material. Grasses like switchgrass, miscanthus and bamboos were tested, but each lacked the desired scalability, sturdiness, and carbon-capturing performance.

They say they eventually came upon an ideal candidate.

Selling tobacco farmers on grass

Last year, Plantd relocated its headquarters 30 miles north to Oxford, a town of 9,000 near the Virginia border. A mural advertising Natural American Spirit cigarettes still covers a wall of the converted Reynolds American facility, which closed in 2022. It is a history Plantd seeks to capitalize on as it convinces farmers around the traditional tobacco hub to produce its particular tall and hard grass.

It hasn’t been an easy pitch; some North Carolina farmers were soured by a push in recent years toward producing industrial hemp. But Plantd has two contracts, including one with 2020 Farmers Cooperative, a nonprofit that works with historically underserved farmers in nine states. In August, Plantd announced its goal to cultivate 550 acres of grass through the cooperative by next year.

“The economic downturn of tobacco left a vacuum of what is available to do in the region,” Tan said. “We see that as an inefficiency. There’s land. There’s infrastructure. We moved in. we started growing from there.”

Plantd estimates an acre of its grass could produce as many panels as 52 trees. The grass is sterile, and to clone it, it opened a tissue culture facility at its Oxford headquarters.

The company has 120 employees. In addition to its main site, it owns a research and development farm in Roxboro, facilities in the Granville County town of Stovall, and an out-of-state raw materials plant.

It has raised $20 million so far and is seeking more funds from investors and government grants. In addition to panels, Plantd is developing housing beams and headers. In time, it wishes to make the entire framing package for single-family houses, multi-family units, and commercial properties. But the D.R. Horton order alone will take the startup multiple years to fulfill.

D.R. Horton has already used Plantd materials in a model home at the Fletcher Mill development in East Durham. The firm nowwants to build 90,000 more.

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