Growing Instead of Firing: When Life Replaces the Kiln

When we think of bricks or concrete, we imagine high-temperature kilns, mineral extraction, and massive CO₂ emissions. Yet, recent research shows that it is now possible to grow construction materials with the help of bacteria.

The process, known as Microbially Induced Calcium Carbonate Precipitation (MICP), relies on the ability of certain microorganisms to precipitate calcium carbonate (CaCO₃) and bind mineral particles together [1].

Bricks Grown from Bacteria

The American company BioMASON, founded in North Carolina in 2012, has demonstrated that it is possible to manufacture bricks without firing, at room temperature, by cultivating calcifying bacteria in sand-filled molds.The process mimics the natural formation of seashells: microorganisms precipitate CaCO₃, acting as a biological cement.

According to tests conducted on the first industrial batches, these bricks reach compressive strengths comparable to conventional products while reducing CO₂ emissions by more than 80% compared to traditional fired bricks.The process requires no kiln or chemical binder only a mineral substrate, nutrients, and a few days of growth [2][3].

Concrete That Heals Itself

Other researchers have focused not on manufacturing, but on regeneration.A 2024 critical review in Science of the Total Environment summarizes the progress made in bacterial self-healing concrete [4].The principle is simple: bacteria are encapsulated within the cement matrix. When a crack appears and moisture seeps in, the microorganisms become active, produce CaCO₃, and seal the gap.

Several studies report impressive results. In one experimental mix, the recovery of compressive strength after 180 days reached up to 92%, thanks to the combined action of CaCO₃ and bacterial activity [5].This self-healing ability could significantly extend the lifespan of structures and reduce the costs and emissions linked to maintenance.

To make these systems more robust, some research teams are developing genetically modified bacterial strains capable of surviving extreme pH levels and reactivating multiple times throughout the life of the material [6].

Biomineralization as a Lever for Sustainability

Genetic engineering applied to construction is not only about creating “smart” materials.It addresses a major environmental challenge: cement production accounts for roughly 8% of global CO₂ emissions, according to the International Energy Agency.

Biological processes such as MICP could cut these emissions by up to 90% by eliminating the firing stage and using low-impact sources of calcium and carbon [7].These materials not only reduce impact, they behave differently.A wall could strengthen itself when exposed to humidity rather than cracking.A brick could be locally grown from sand and nutrients, transforming production cycles into constructive ecosystems.

Case Studies

The first case, BioMASON, has already crossed the threshold from laboratory to market.In 2023, the company announced a production line capable of manufacturing several thousand bricks per day. Each unit forms through bacterial precipitation in less than a week without combustion, gas, or industrial kilns. This achievement proves that biomanufacturing can reach commercial scale while massively reducing emissions [2][3].

The second example, drawn from the 2024 review on self-healing concretes, demonstrates the concept’s feasibility in structural applications.The most effective formulations regained nearly all of their strength after cracking, thanks to encapsulated bacteria capable of reactivating months after casting [5].At scale, such materials could dramatically extend infrastructure lifespans and reduce the demand for new cement one of the sector’s largest carbon contributors.

Between Laboratory and Construction Site

These breakthroughs are promising but present major challenges. Most experiments are still carried out on a small scale, under controlled conditions. Industrialization will require mastering bacterial viability over decades, ensuring uniform distribution within the cement matrix, and meeting existing performance standards. Regulation is another hurdle: current building codes do not yet account for “living” materials. As the 2024 Advances in Microbial Self-Healing Concrete review highlights, certification and biosafety remain among the main obstacles to widespread adoption [4][6].

Behind these innovations lies a new philosophy of construction. Where traditional concrete depletes and traps, biological materials reintroduce active circularity. A wall is no longer a static structure it becomes a mineral organism that interacts with its environment.

Researcher Zuo (2023) notes that controlled biomineralization now extends across multiple domains, from soil stabilization to bio-brick production, and stands among the most promising research fields of the decade [7]. The future may even see the emergence of programmable materials, capable of adjusting their behavior according to light, temperature, or pollution, paving the way for a truly living architecture.

Conclusion: Toward a Living Architecture

From bricks grown at room temperature to concretes that heal themselves, the studies cited point to a turning point: an architecture that collaborates with life.BioMASON has proven that it is possible to produce durable, low-carbon bricks at scale without kilns or cement [2]. The 2024 critical review showed that concrete can recover up to 92% of its strength after cracking, thanks to bacterial action [5]. Although still experimental, these figures reveal a deep transformation: matter becomes active, reactive, almost autonomous.

Industrial scaling, regulation, and public acceptance remain ahead, but one thing is clear: building sustainably will no longer mean making inert materials; it will mean creating materials capable of living, evolving, and enduring. Genetic engineering applied to construction is not a scientific curiosity it signals the rise of a new ecology of the built environment, where stone breathes, concrete heals, and the living itself becomes a construction material.

Sources

[1] Lambert, S. E., Randall, D. G. (2019). Manufacturing bio-bricks using microbial induced calcium carbonate precipitation (MICP). Journal of Water Research, Elsevier.

[2] BioMASON Inc. (2023). Biobrick Production Overview. BioMASON Corporate Report.

[3] Smirnova, M. et al. (2023). High strength bio-concrete for the production of building materials. Nature Scientific Reports.

[4] Liang, J. et al. (2024). Advances in microbial self-healing concrete: A critical review of challenges and prospects.Science of the Total Environment, Elsevier.

[5] Estupiñan, R. A. et al. (2023). An autonomous system to bio-bricks production by microbial induced calcium carbonate precipitation (MICP). Brazilian Journal of Development.

[6] Qian, C. et al. (2023). Genetic improvement of Bacillus subtilis for enhanced biomineralization in self-healing concrete. Journal of Industrial Microbiology & Biotechnology, Oxford University Press.

[7] Zuo, R. (2023). An assumption of in situ resource utilization for bio-bricks: Microbial induced calcium carbonate precipitation as sustainable construction material. Frontiers in Materials.