The majority of buildings use energy-intensive Heating, Ventilation, and Air Conditioning (HVAC) systems to maintain healthy and conformable spaces inside. The goal of this project is to develop lichen-inspired surfaces that are energy-efficient, capable of removing indoor pollutants, and maintain comfortable indoor humidity levels. In nature, lichens are complex communities of microbes that can absorb moisture and contaminants in the air with sunlight as their primary energy source, making them an ideal candidate for reducing the energy cost of maintaining indoor air quality. Yet, natural lichen is very slow-growing and is difficult to grow indoors. This work uses synthetic biology to engineer industrial microbes to create lichen-inspired surfaces on various building materials (wood, stone, brick, concrete). The project will study how these lichen-inspired surfaces remove pollutants and control humidity levels to enhance indoor air quality. Indoor environmental quality (IEQ) is a central determinant of human health and quality of life in the modern world, and maintaining it consumes 40% of the energy in the US. The goal of this project is to determine fundamental design principles for sustainable bioactive surfaces that improve IEQ. This work is inspired by lichens, a symbiotic consortium of cyanobacteria, fungi, and other microbes. Their resilience to environmental fluctuations and capacity to colonize building materials without exogenous inputs make them a promising mat