Research

Livia Kalossaka

Functionally optimized biofilms for building fa├žades

Livia Kalossaka - 1st year PhD

Abstract

Building façades remain one of the most important exterior elements for building functionality. While the façade can be an elegant component that helps to define the unique architectural aesthetics of the building, it also has critical roles such as building protection, energy performance and interior function of a building. As technology continues to improve, different options for improvement become available for incorporation into building facades. An exciting avenue for novel building facades is the use of bio-materials or bio-receptive materials that incorporate, and harness, living systems to improve façade performance.
A biofilm is any group of microorganisms in which cells stick to each other and often these cells adhere to a surface. An established biofilm comprises microbial cells in a defined architecture and provides an environment conducive to cellular communication via exchange of genetic material or quorum sensing. Increasingly knowledge in biotechnology allows us to further imagine how bacteria and their biofilms may be manipulated, their communication pathways intercepted, and their unique properties harnessed for human-orientated design and engineering. Their contribution to design and engineering, particularly in their incorporation with materials is likely to become more widespread.
Some examples of the means by which bacteria may be integrated into facades are as follows: organisms that feed off solar energy could be designed as self-repairing paints, or organisms that obtain their energy from oxidation of a material donor could be employed as anti-wear/anti-corrosion coatings; even in underwater environments.
Building exteriors are an underutilized canvas that could provide a rich environment for cellular bionic systems in the following means: protection of building surfaces from weathering, the cleaning and repairing of exterior surfaces, the control of indoor temperatures and comfort, and by providing smart fire defenses.  In addition, cellular bionic building facades present an opportunity to create something delightful such as colourful designs that alter appearance and adapt with their surroundings, the weather and changing fashions. This project presents a novel definition of ""smartness"", one that harnesses the embodied intelligence of bacterial organisms and their biofilms. Bacteria can react to novel stimuli in real-time, reproduce and self-repair as well as learn behaviour according to environmental circumstances. The possibility that we may create bio-facades that can communicate to their user, provide feedback and adapt to their environment proposes an initial step towards an exciting vision of the smart city of the future.
This project will investigate the potential use of bio-receptive materials capable of growing microorganisms directly onto their surface as novel cladding systems. This system will go beyond the current limitations of green walls, with the accompanying need for mechanical irrigation systems and expensive maintenance, and design cellular symbiotic systems that feed off their surrounding environment. Instead of building against nature, biological materials and processes will be integrated into structurally engineered materials and processes. By designing surfaces that are bio-receptive we will carefully select and grow bio-films that perform a desired function actively delivering a beneficial system. The project intends to overcome many of the limitations of existing 'green walls'; particularly the need for mechanical irrigation systems and expensive maintenance.