Studies have shown the biome of the gut is critical to human health. Scientists have found there are good bacteria that promote health and bad bacteria that can play a factor in disease. With the growing use of supplements like probiotics, the idea to create an environment in the gut that encourages good bacteria growth has gained acceptance in the general public. 

Ted Krueger, an associate professor in the School of Architecture at Rensselaer Polytechnic Institute, would like people to take that same concept and apply it to buildings.

“Bacteria already exist on the walls and in the corners of rooms we are trying to sterilize,” Krueger says. “Stop declaring war to annihilate the entire community of microbes. Shift perspective and find ways to provide for the needs of beneficial microorganisms. This will be more effective and sustainable into the future.”

Krueger says that one of the difficulties in treating unwanted microbiological inhabitation is that the microorganisms rarely exist in isolation as single organism colonies, but instead as communities. As is the case when treating humans with antibiotics, a disruption of a community will not necessarily result in its permanent disappearance and upon re-establishment, it might lead to the development of bacteria that are resistant to the methods used to rid the environment of the bad bacteria.

Instead, Krueger advocates for creating an environment where the good microbes are happy. He cites the culinary model of cheesemaking as a good example.

“Great cheesemakers have to sanitize, but at the same time they know their house ecology is very specific and that’s what makes them famous,” Krueger says. “What we need to do is make spaces that are dominated by ecologies of good bacteria, the ones we get along with, and they’ll defend the space and create an environment healthy for humans.”

The idea has potential for contemporary impact in the built environment as scientists and architects look to combat the current COVID-19 pandemic.

 “There are no sterile conditions, at least, not for long,” Krueger says. “The image of walls thickly covered with microorganisms, especially in medical contexts, might be disconcerting to some, but those spaces are already inhabited. The task might be to learn a new form and scale of agriculture – a micro-agronomy – that could be fostered and cared for in return for its benefits. Microbes could become an immune system for the built environment.”

Krueger’s faculty page can be found here:

More info on Krueger’s ideas can be found in “Microecologies of the Built Environment,” a chapter in the book, The Routledge Companion to Biology in Art and Architecture.