Bio-Based or Bust

Before World War II, many buildings around the globe were constructed from natural materials like wood, stone, and thatch. These structures suited local climates. Some 
decomposed and returned to the earth over time, while others endured for hundreds, even thousands, of years.

After the war, organic building elements were replaced by steel, concrete, and cheap synthetics—many made from petrochemicals. Today, synthetic carpeting, vinyl window frames, and resilient flooring are ubiquitous and inexpensive up front, but they also contribute to greenhouse gas emissions and can introduce dangerous chemicals like PFAS into the built environment.

For years, environmentally conscious designers and builders who championed a return to natural materials like straw and earthen plaster were dismissed as niche. But no longer. A new generation of bio-based products is coming online, offering the co-benefits of protecting human health and decreasing the climate impact of buildings, which are collectively responsible for nearly half of all global carbon emissions.

Gordon Boggis, the CEO at Carnegie, a manufacturer of sustainable textiles like the fabric Xorel, said plant-based materials are key to driving the construction industry toward circularity. “By default, we have an ingredient set which is less hazardous.”

Going all natural

Many bio-based building products have low carbon emissions and are nontoxic and fully compostable or biodegradable. They’re also attractive and perform just as well as their synthetic counterparts: Think foam insulation grown from mycelium, wall panels made of wood and straw, and bricks made with algae.

Hempcrete, manufactured by combining the woody portion of hemp stalks with a quicklime-based binder, can be sprayed into walls or formed into blocks that are used for insulation. Biochar, produced by burning organic materials like wood chips in an oxygen-starved environment, can replace some of the cement in concrete, significantly lowering its carbon footprint.

A new generation of bio-based products is coming online, offering the co-benefits of
protecting human health and decreasing the climate impact of buildings.

Often, waste from agricultural crops serves as a source material. Carnegie’s Xorel, for example—used as upholstery, acoustic panels, and wall coverings—is made from the fermented juice of crushed sugarcane.

The potential is enormous: According to the clean energy nonprofit RMI, some 400 million tons of existing biomass waste could be transformed into usable products.

Confronting barriers

If bio-based materials are becoming more widely available, why aren’t people using them? Oftentimes, it’s because legacy building codes haven’t caught up—they may not recognize so-called alternative construction methods. Meanwhile, manufacturers can’t always keep up. For example, they may not have access to the machines that strip bark from the inner woody core of hemp plants.

James Kitchin, director of the Abundant Futures Design Lab at Model of Architecture Serving Society, had successfully practiced bio-based construction in Rwanda. But when he began working in the United States, he quickly ran into barriers. In one case, when trying to incorporate straw panels into an affordable-housing project in Boston, clients balked at the upfront cost and thickness of the material.

“At the same time, I was seeing seven-story straw buildings going up in France and 50-unit hempcrete housing developments in Switzerland,” Kitchin said.

In 2023, Kitchin helped establish the Bio-Based Materials Collective, a diverse group including builders, academics, harvesters, and cultivators, to identify barriers to wide-scale adoption of bio-based materials. The collective brings people from siloed parts of the industry together to help identify bottlenecks and work on solutions. They also advocate for the inclusion of bio-based materials in building codes.

“When it’s in the code, it just suddenly becomes so much easier,” Kitchin said.

Renovating sustainably

Bio-based materials are so common now that homeowners can incorporate them, no matter how big or small the renovation. If you are just replacing carpet in a bedroom, retiling a bathroom, or updating your countertops, you should be able to find bio-based alternatives to cheap petrochemical options.

If you are working with an architect or interior designer, ask if they are familiar with bio-based materials. Try to implement them into the plans where possible. Next, look for a builder who has experience handling those ma­terials. Ask if they are familiar with sustainable or passive (energy efficient) construction methods. Or consult local green building councils for suggested contractors in your area.

“Even when sustainability goals are strong, design teams often default to familiar materials because they feel more predictable and are easier to justify internally across clients, consultants, and contractors,” said Kristen Hayes, director of brand strategy and partnerships at Ekoa by Lingrove. The California-based company makes a sheet material out of flax—a fast-growing crop that requires few, if any, chemical inputs—for walls and cabinets.

If you are working directly with contractors or tradespeople for a small job like a basic bathroom renovation, you can purchase sustainable bio-based options yourself. Check out Greenbuildingsupply.com to help source your own materials.

Beware of greenwashing! Third-party certifications can help verify environmental claims. The Greenguard ecolabel means that a product has no or low VOC emissions. The Declare ecolabel discloses product ingredients.

You may find that your designer or contractor is ready to get back to bio-basics. If they aren’t, be the change: Help open their eyes to a plant-based material world.