The construction industry has historically been one of the largest emitters of CO2, largely due to the energy-intensive process of manufacturing traditional concrete and clay bricks. But as we enter 2026, a biological revolution is taking place on British building sites. Mycelium masonry—the practice of “growing” structural bricks from the root systems of mushrooms—has moved from experimental labs to mainstream architecture. These fungi-based bricks are now being used to construct the UK’s greenest homes, providing a carbon-negative, high-performance alternative to traditional materials.

The process of creating mycelium masonry is as fascinating as it is sustainable. Organic waste, such as agricultural straw or hemp husks, is placed into a mold and inoculated with specific mushroom spores. Over the course of a few days, the mycelium (the root structure of the fungi) grows through the waste, binding it together into a solid, durable block. The process is then halted using heat, leaving behind a lightweight, fire-resistant, and incredibly strong brick. Because these fungi-based bricks grow at room temperature and consume waste products, their production actually removes more carbon from the atmosphere than it creates. This is why they are the foundational material for the UK’s greenest homes.

The performance of mycelium masonry is surprising many traditional builders. These bricks have natural insulation properties that far exceed those of concrete or wood. They are also naturally “breathable,” meaning they regulate humidity within a building, preventing mold and improving indoor air quality. For the residents of the UK’s greenest homes, this means lower energy bills and a healthier living environment. Furthermore, fungi-based bricks are biodegradable at the end of their life cycle. If a building is demolished, the bricks can be shredded and returned to the earth as nutrient-rich compost, completing a perfect “cradle-to-cradle” loop.