In their most famous works, Fernando and Humberto Campana construct by a process of accumulation, looping yards of sail rope around seat frames or folding velvet tubing in on itself to create amoeba-like sofas.

So it’s fitting that visitors to the brothers’ São Paulo studio should find behind its unremarkable metal grate rooms and shelves stacked high with stuff — weird material experiments by the studio’s half-dozen in-house artisans, miniature models and prototypes, artifacts the brothers picked up on their travels, miles of scrap, and dozens and dozens of sketches. In some ways, it all seems an extension of São Paulo itself, a city of 20 million that in the last century has sprawled so far and wide it’s annexed, at last count, five different downtown areas. (The Campanas live and work in Santa Cecília, or as Fernando calls it, “second downtown.”)

The Campanas’ studio is hidden behind an old garage door in the Santa Cecília neighborhood of São Paulo. “Chauffeurs arrive, they think it’s not here, and they don’t drop the clients off!” laughs Fernando. “But we didn’t bother to paint the facade. It’s the best way to live free and at peace in Brazil. You can’t show off. If I go out, I don’t wear jewelry or anything that will attract attention. Usually, people either think I’m a policeman or a robber.”

Read more about the duo’s biography, workspace and upcoming project here on SightUnseen