A. J. Lode Janssens (b. 1947) is one of Belgium’s most idiosyncratic architects and a radical educator. He was co-founder of the experimental studio Atelier Alpha and the Sint-Lucas Werkgemeenschap, a workshop linking architectural education, practice, and research, and operated in close collaboration with ILAUD, the International Laboratory of Architecture and Urban Design. The publication A. J. Lode Janssens 1,47 mbar presents ”The Balloon“, an all-but-unknown temporary pneumatic home experiment, built in 1973 in Humbeek, where he lived with his family until 1986. Lode Janssens considered it an uncompromising ephemeral attempt at de-architecturalization and living in harmony with nature: a cave-dwelling, a work-in-progress, an empirical residence.