Rael San Fratello tests new materials and public ideas in YBCA retrospective

A roof assembled from discarded broom heads and walls printed from biodegradable thermoplastic sit alongside earthen structures, political interventions and experimental objects in a retrospective of Oakland studio Rael San Fratello. Prototypes and Provocations surveys more than two decades of work at Yerba Buena Center for the Arts in San Francisco.

Founded in 2002 by Virginia San Fratello and Ronald Rael, the practice moves between architecture, design and social practice. The exhibition, curated by René Morales, brings together built work, prototypes, models and projects that test how material choices and construction technologies can respond to urgent social questions.

Earth, technology and repair

A new commission, Sanctuary, anchors the presentation. The cylindrical structure was 3D printed on site from a mixture of soil, straw and water, then capped with a mirrored inflatable orb. Glass tubes salvaged from Solyndra, the California solar-panel manufacturer that went bankrupt in 2011, puncture its earthen walls. The installation places an ancient building material beside the remnants of a recent clean-energy venture, asking what societies preserve, discard and give another use.

The studio’s interest in material reuse continues in The Workshop, commissioned by YBCA. Recovered broom heads form its roof, while an undulating shell of PLA filament, a bio-based thermoplastic, wraps the structure alongside small planter boxes. Nearby displays extend the experiments to 3D-printed objects made with coffee grounds, Chardonnay grape skins and ash gathered after California wildfires.

Design as a public act

Other works address migration, protest and the US–Mexico border. Teeter-Totter Wall revisits the bright-pink seesaws that crossed openings in the border barrier in 2019, allowing people on either side to play together. The exhibition also presents inflatable Tyvek coats designed as temporary shelters and REUNITE, an open-source image of a family running toward one another, made available for use in demonstrations.

Across these projects, Rael San Fratello treats architecture as a means of making ideas tangible and shared. The retrospective connects material research with questions of access, environmental responsibility and political division, while showing how prototypes can invite people to imagine different ways of building and living.

Project Credits

Exhibition: Rael San Fratello: Prototypes and Provocations
Design studio: Rael San Fratello
Curator: René Morales
Venue: Yerba Buena Center for the Arts, San Francisco, United States
Dates: 25 September 2026–31 January 2027
Photography: Matthew Millman / @matthewmillmanphoto