The 1.1 billion tons of biomass that could revolutionize construction
The buildings we inhabit come with a hidden environmental price tag. Globally, the construction sector accounts for at least 37% of all greenhouse gas emissions 1 . Each new home built in the United States contributes to an estimated 55 to 80 million tons of embodied carbon emissions annually—comparable to the total annual emissions of entire countries like Norway, Hungary, and Austria 2 .
This "embodied carbon" includes all greenhouse gases released throughout a building's life cycle, from material extraction and manufacturing to transportation and eventual disposal 1 .
Meanwhile, as demand for housing continues to grow, an unexpected solution is piling up in plain sight: the United States generates over 1.1 billion tons of biomass annually from farms, forests, and landfills, much of which currently has little to no market value 1 2 . What if we could transform this agricultural waste into the very materials we need to build our homes?
Bio-based construction materials are derived from renewable biological resources rather than finite, extracted materials. These include familiar materials like timber and straw alongside innovative newcomers like hempcrete and mycelium insulation 5 .
Roughly 50% of the weight of plants is photosynthetically sequestered carbon, meaning these materials actively pull carbon dioxide from the atmosphere as they grow 1 .
When we use these plant-based materials in construction, we effectively lock away that captured carbon for the lifetime of the building—potentially 50 to 100 years or more 2 . This transforms our buildings from carbon sources into carbon sinks, fundamentally changing their relationship with our atmosphere.
| Attribute | Traditional Materials | Bio-Based Materials |
|---|---|---|
| Carbon Impact | High embodied carbon | Carbon sequestering |
| Resource Basis | Finite extraction (mines, quarries) | Renewable biomass |
| Common Examples | Concrete, steel, synthetic insulation | Hempcrete, straw panels, mycelium |
| End-of-Life | Often landfill | Typically biodegradable or reusable |
| Production Energy | Energy-intensive | Minimal processing required |
The range of biomass that can be transformed into building materials is as diverse as it is surprising:
A natural by-product of wheat, rice, rye, and oats, sequesters 60 times more carbon than it requires to grow, making it one of the most powerful carbon-storing building materials in the world 1 .
When compressed into panels or used in bale construction, it provides excellent thermal insulation, helping buildings stay warm in winter and cool in summer 1 5 .
Carbon NegativeMade from the woody core of the hemp plant mixed with lime and water, is a lightweight, fire-resistant material that actually absorbs more CO₂ than it emits during its production, creating a carbon-negative building component 5 .
At the end of its life, it can be crushed and reused or returned to the earth.
Carbon NegativeThe root-like structure of fungi, is being developed into insulation products that can break down toxic compounds during production while providing higher insulation values than many synthetic alternatives 9 .
Mycelium insulation naturally decomposes at the end of its useful life, creating zero waste.
Biodegradable| Biomass Source | Type | Common Applications | Key Benefits |
|---|---|---|---|
| Grain Straw | Agricultural residue | Strawboard panels, bale construction | Excellent insulation, carbon sequestration |
| Hemp Hurds | Fiber crop by-product | Hempcrete blocks, insulation | Fire-resistant, carbon-negative |
| Mycelium | Fungal fibers | Insulation panels | Biodegradable, toxin-absorbing |
| Timber Thinnings | Forestry by-product | Structural panels, flooring | Improves forest health, renewable |
| Recycled Paper/Cardboard | Post-consumer waste | Cellulose insulation | High recycled content, low embodied energy |
Even more unconventional materials are entering the market. Companies like Biohm are creating cork-like boards from orange peels collected from cafeteria waste and converting grass clippings from airports into building panels 9 . These innovations not only reduce construction emissions but also divert organic waste from landfills where it would release methane—a potent greenhouse gas.
In 2025, researchers at ETH Zurich unveiled a groundbreaking development that blurs the line between building material and living organism: a printable gel infused with ancient cyanobacteria that actively captures CO₂ from the air 8 .
The research team, led by Professor Mark Tibbitt, followed these key steps in developing their revolutionary material:
Researchers created a gel from cross-linked polymers with high water content, specially designed to transport light, CO₂, water, and nutrients while allowing cells to spread evenly 8 .
Photosynthetic cyanobacteria—among the oldest life forms on Earth—were stably incorporated into the hydrogel. These microorganisms are highly efficient at photosynthesis, utilizing even weak light to produce biomass from CO₂ and water 8 .
Using 3D printing, the team created structures with optimized geometry to increase surface area, enhance light penetration, and promote the flow of nutrients through capillary forces without requiring active pumping 8 .
As the cyanobacteria photosynthesize, they alter their chemical environment, causing solid carbonates (similar to lime) to precipitate within the material. These minerals serve as an additional carbon sink while mechanically reinforcing the initially soft structures 8 .
The living material demonstrated remarkable capabilities during laboratory testing:
This performance is significantly higher than many biological approaches and comparable to the chemical mineralization of recycled concrete 8 . The real-world potential was demonstrated through architectural installations, including "Picoplanktonics" at the Venice Architecture Biennale, where three-meter-tall, tree-trunk-like structures each capture up to 18 kg of CO₂ per year—equivalent to a 20-year-old pine tree 8 .
| Material/Approach | CO₂ Sequestration Capacity | Storage Form | Duration |
|---|---|---|---|
| ETH Zurich Living Material | ~26 mg/g | Biomass & minerals | 400+ days |
| Chemical Mineralization (Recycled Concrete) | ~7 mg/g | Minerals | Permanent |
| Standard Concrete | None - emits ~900 kg CO₂ per ton | N/A | N/A |
| Straw Building Materials | 60x more carbon stored than emitted to produce | Plant biomass | Building lifetime |
The potential impact of widespread adoption of biomass building materials is staggering. Research from RMI indicates that if just 25% of new American homes used bio-based products by 2050, we could store a stunning 100 million tons of carbon—equivalent to the tailpipe emissions of 21 million cars 2 . At 75% uptake, that total jumps to 300 million tons of carbon storage 2 .
| Adoption Scenario | Carbon Storage Potential | Equivalent Car Emissions Removed | Timeline |
|---|---|---|---|
| 25% of new homes | 100 million tons | 21 million cars | By 2050 |
| 50% of new homes | 200 million tons | 42 million cars | By 2050 |
| 75% of new homes | 300 million tons | 63 million cars | By 2050 |
Bio-based materials are typically non-toxic and emit fewer volatile organic compounds (VOCs) than many conventional materials 5 .
Materials like hempcrete and clay demonstrate excellent fire-resistant properties, a valuable consideration in wildfire-prone areas 1 .
At the end of their life, many bio-based materials can be composted or reused, eliminating construction waste 1 .
Potential carbon storage from bio-based material adoption in US home construction:
Equivalent to removing 63 million cars from the road annually
"You're taking what would be an agricultural waste product that might break down in the field, and you're putting it into a building. You're storing carbon in buildings."
While challenges remain—including scaling up production and updating building codes—the foundation has been laid for a transformative shift in how we build 1 4 . From 3D-printed living materials that breathe in CO₂ to insulation grown from fungi, the future of construction is taking root in unexpected places: our farms, our forests, and even our waste streams.
In the effort to rebuild our world more sustainably, the solutions may have been growing around us all along.