The sulphur concrete block came out of various experiments performed by the Minimum Cost Housing Group at McGill University in Montreal in the 1970s. moreThe international research group explored self-building using materials that would present an alternative to the functionalistic logic of development aid programmes tied to the Western construction industry. The ”Other Half“—a term that was coined to describe decolonized countries and urban populations living in informal housing at the time—was the focus of their experiments with alternative building solutions. Beginning with an understanding of how and why the block was made, its actual usage, and its afterlife and going on to examine its archival status and symbolic relevance within architectural historiography, shaped by a paradigm shift in our overall view of ”Habitat,“ the book shows how the block became both a vessel and vector for the projections and questions explored by the transdisciplinary group of the Bauhaus Lab 2020.