He Quit SpaceX To Make Homes From Grass

Summary

Nathan Silvernail explains why he left SpaceX to co-found Plantd, a company developing structural building panels from fast-growing perennial grass. His central business thesis is that industrial change depends not only on creating a more sustainable product, but also on improving its economics and fitting it into customers’ existing workflows.

Strategy and go-to-market

• Make adoption feel like business as usual. Plantd chose oriented strand board (OSB) as its first product because it can serve as a drop-in replacement for timber-based panels. The company designed it to match existing panel weight and construction practices while preserving permitting, inspection, and certification processes.
• Compete on economics as well as performance. Silvernail’s approach is to make the product cheaper and better without requiring builders to change their behavior. He argues that a sustainability benefit alone is not enough to overcome an entrenched market.
• Use customer feedback to define the product. Plantd initially developed a grass-based material with a very high strength-to-weight ratio. D.R. Horton’s response—that builders would not buy it just because it was stronger—helped Plantd refocus on a familiar, practical OSB replacement.
• Secure an internal champion. Silvernail credits D.R. Horton’s partnership with helping Plantd understand builders’ needs and shape a viable adoption path.
• Use unit economics to challenge incumbents. Silvernail draws a parallel with SpaceX’s challenge to established launch providers: a large cost advantage can create traction and make it difficult for incumbents to compete. Plantd aims to use price and production efficiency to win lumber-market share.

Plantd’s product and operations

• Plantd says its panels are intended for the structural parts of homes—floors, walls, and roofs—rather than visible, style-driven features such as exterior railings.
• Silvernail claims the panels outperform timber-based alternatives on strength, moisture resistance, rigidity, manufacturing efficiency, and cost. The subtitles do not provide quantified test results for these comparisons.
• The company’s production concept uses grass that is close to its required moisture level at harvest, reducing the need to burn biomass to dry the material. Silvernail says engineered-wood producers use about 20% of their biomass for drying.
• Plantd is developing a circular manufacturing loop: unavoidable production waste is gasified into a carbon product, currently used as biochar, which is returned to the fields to support soil health.
• Plantd works with John Deere on modified harvesters. Harvested grass is cut, loaded into trucks, and taken to the processing plant.

Biomass selection framework

Plantd assessed possible feedstocks against three core requirements:

• Structural: The material must meet building-panel requirements.
• Economic: It must be practical to process at scale and support positive margins.
• Carbon-negative and durable: The carbon stored in the material must outweigh production emissions, and the structure should retain that carbon over a long service life.

The company tested mycelium, hemp, bamboo, and other biomasses. Silvernail says mycelium lacked the needed structural properties; hemp was difficult to process at scale and included a large unusable portion of the plant; bamboo’s density created processing and tooling costs; and annual-seed crops such as corn did not fit the desired production model.

Agricultural model and metrics

• Plantd reports a 9×–15× land-use advantage per acre compared with tree species.
• Its grass can be harvested after about nine months, compared with roughly 15 years for loblolly pine.
• The crop is perennial and rhizome-based. Silvernail says fields can produce for about 20 years, with yields increasing until around year four or five.
• In North Carolina, production is seasonal. Plantd plans to expand along the I-85 corridor toward South Florida to reduce the impact of winter dormancy.
• At around 20–25 years, the company says it can use a field-renewal process to extend production without digging up the plants and disturbing the soil again.
• Silvernail says Plantd’s production capacity for the next 10 years is accounted for and describes demand as effectively unlimited. These are company statements, not independently verified forecasts.

Actionable business lessons

• Start with a clear requirement matrix before choosing a technology or feedstock.
• Build a workable product first; optimize it through iteration rather than waiting for a perfect solution.
• Design around customers’ current standards and processes when those systems are hard to change.
• Let customer feedback challenge engineering assumptions—even an objectively stronger product may not be the product the market wants.
• Treat unit economics as a core lever for disrupting established industries.
• Be prepared to pivot: Silvernail says his engineering and aerospace experience transferred to a very different industry.

The discussion also uses the Space Shuttle as an example of a capable technology that was discontinued largely because its unit economics did not work. The broader point is that technical performance alone does not ensure commercial viability.

Presenters and sources

Presenters: Hosts Mark and Jeremy; guest Nathan Silvernail, Plantd co-founder.

People and organizations mentioned: Huade Tan (Plantd co-founder and CTO), SpaceX, NASA, United Launch Alliance (ULA), D.R. Horton, and John Deere.