Bio-Block™ Spiral has opened to the public at 167 Green Street for the fifth edition of the Chicago Architecture Biennial. Constructed out of Bio-Blocks—an algae-based concrete alternative developed in partnership with Prometheus Materials—the installation offers a model for carbon-neutral construction.

Reflecting on the Biennial theme, This is a Rehearsal, Bio-Block Spiral demonstrates a change-making collaboration across construction, fabrication, and design industries as a precursor for a healthier world. The installation creates a public space for gathering and contemplation in Chicago’s Fulton Market District.

Composed of algae-based bio-concrete, the zero-carbon Blocks could significantly reduce global CO2 emissions if deployed as an alternative to Concrete Masonry Units, one of the most prevalent building materials. To underscore the viability of this replacement, the installation was assembled using conventional masonry techniques and constructed by the International Masonry Institute and J&E Duff.

Bio-Block Spiral invites Biennial visitors to not only see and touch the Bio-Block, but to also observe how the construction responds to wind, moisture, and temperature fluctuations during Chicago’s fall months. Echoing the shell-like material composition of the bio-cement, SOM conceived of a spiraling form that invites Fulton Market visitors to step off the busy street and explore the installation. A central space offers views to Halsted Street using rotated blocks at regular intervals to create apertures, underscoring the simplicity of the block-and-mortar construction. Pleated ends demonstrate the versatility of the block form and improve the structural stiffness of the installation, allowing the Spiral to be self-supported. A film projected on the wall highlights both the proprietary manufacturing and the conventional construction processes of the Bio-Block Spiral.

The installation applies SOM’s collaborative and ongoing research on bio-materials. Bio-Block Spiral is the third consecutive installation that SOM has presented at the Chicago Architecture Biennial to demonstrate innovative approaches to low-carbon construction, following the SPLAM timber pavilion in 2021 and Stereoform Slab in 2019. 

Bio-Block Spiral is on view at the Mews at 167 N Green Street in Fulton Market, Chicago.