By Erica Rascón, Contributing Writer
Imagine a future where one simple building material provides structural integrity, stellar interior climate control, and atmospheric carbon dioxide reduction. For builders investing in living concrete, the future is now.
Structural Technology Group of Universitat Politècnica de Catalunya (UPC) in Barcelona, Spain, recently created living concrete, a technological breakthrough that fulfills three distinct purposes in one convenient and versatile package. The concrete serves as a reliable façade material, insulation, and air filter. Three layers compose the living concrete system. A waterproof membrane rests at the base. It creates a barrier that protects the housing structure from exterior elements. This layer also serves as the foundation for the biological concrete.
A special concrete mixture with a low pH is then applied on top of the membrane. Higher levels of magnesium phosphate cause the substance to have a naturally lower pH, which creates a habitat appropriate for select plant life such as mosses, lichen, and algae. The concrete is designed to retain moisture, nourishing the plants while creating a solid façade for the structure.
Lastly, a porous coating tops off the design. This layer specializes in harvesting available moisture from the surrounding environment and channeling it to the base membrane. Both the retained water and the biological organisms help to insulate the building, promoting a controlled climate for the building’s occupants.
Structures completed with living concrete will actively work to reduce carbon dioxide levels in the atmosphere. The plant life that grows on the concrete system absorbs CO2 while creating fresh oxygen. This features makes living concrete an ideal material for buildings in urban settings where carbon dioxide levels are often higher.
Living concrete provides the builder with a relatively lightweight and self-sustaining system. Unlike vertical gardens or other vegetated walls, there is no need for supplemental support systems that can add bulk to a building or limit its application to existing structures. Marginal maintenance keeps the structure beautiful year round.
UPC is currently developing variations of living concrete that foster particular types of plant life, helping builders control the appearance of the structure. As seasons change, the biological organisms growing on the surface may also change, allowing the building to adapt to the seasons, so to speak. The structure will be a responsive part of the community rather than an inanimate bystander. Customizable exterior elements will also permit more predictable control over energy savings.
Living concrete faces a few limitations. Buildings in Mediterranean climates are first to benefit from the material. Such climates provide the ideal combination of moisture and sunlight to help the biological organism thrive. To date, concrete variations for drier and colder climates are not available.
Researchers have not explained how the living concrete definitively deters the growth of unwanted biological organism such as mold, weeds, and the less aesthetically pleasing forms of fungus. UPC press release states, “other types of vegetation are prevented from appearing, lest their roots damage construction elements” though no further comments have been made.