MycoToilet is a modular building that uses living mycelium to transform human waste into a nutrient-rich soil that can be returned to local ecosystems. An interdisciplinary research collaboration between architecture and microbiology, the modular building provides a self-contained composting solution for parks, municipalities and remote communities that lack access to centralized sewer treatment systems. The MycoToilet reframes a fundamental human activity as an act of ecological care and reciprocity.

The prototype is installed in the mature forest of a botanical garden on the campus of the University of British Columbia. An accessible ramp elevates visitors over the ferns of the forest floor, leading to a ventilated sliding door. Inside, light from a circular skylight above falls onto planed timber panels. A planted roof provides visual continuity with its forested surroundings while keeping the interior cool. A silent ventilation system ensures a supply of fresh, clean air to the interior. The design of the project elevates a practical necessity to a restful experience integrated with the natural beauty of the garden, providing a new perspective on a basic human requirement.

The circular ethos of the project is reflected in the materials, which were chosen for durability and low environmental footprint. Cross-dowel timber (XDT) panels that require no glue or fasteners were milled with CNC machine tools and assembled offsite. The timber structure is clad with a cedar rain screen, which has been charred at the base to further improve its natural resistance to decay. Inside, a conveyor separates liquid from solid waste. Solid waste is conveyed to living mycelium containers that promote aerobic waste breakdown, avoiding the odours associated with anaerobic digestion. Liquid waste is stored in a self-sterilization tank prior to use as a nitrogen rich fertilizer.

3.4B people globally lack access to adequate sanitation, which the United Nations defines as a basic human right. The MycoToilet suggests that a response to this issue can be beautiful as well as effective.