In Paris, as in most cities where the architecture has stood the test of time, aesthetes bemoan the inevitable renovation projects that replace aging, stately facades with updated materials. Yet modern-day energy efficiency requires it, and, well, time marches on.

But when Paris-based designer and doctoral researcher Anna Saint Pierre saw the massive granite slabs that were slated to be replaced with thermo-efficient metal panels in the conversion of an old building into a new co-working hub, she started asking herself: Could that granite—all 182 tons of it—be repurposed on-site? And was there a way to create a beautiful new material from it that conserves resources and preserves history all at once?

Saint Pierre was aptly situated to experiment with the concept, given her work-study position at SCAU, the architectural firm tasked with updating the building. In collaboration with her colleagues, Saint Pierre came up with a way to accomplish her idea for recycling in situ—by treating the renovation site as a quarry, sourcing rubble from out of its depths, and breaking it up further to mix with concrete and make a terrazzo flooring she calls Granito.

Both poured and polished on-site, Granito incorporates varying sizes of granite, from the easily identifiable fragmented blocks found in flooring destined for the building’s entrance to the finely ground particles on the lowest floor, where the mineral quite literally has been returned to dust.

Saint Pierre’s Granito is scheduled to debut in December 2020, when the atrium floor will be unveiled. But the concept of in situ recycling is already being applied to future SCAU projects, and Saint Pierre foresees its long-term benefits.

“The building sector represents fifty percent of natural resource consumption and almost forty percent of waste production within European territories,” she says.

“In situ recycling can be seen as a solution to this mass production of rubble. And as such, the demolished building physically informs the concept and look of the new one.”

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