Illustration by Jason Lee

In 2008, designer-architect Robert Couturier landed a dream project: a London-based family’s second home in an iconic Herzog & de Meuron building downtown. It was to be a 2,400-square-foot, south-facing three-bedroom floor-through splashed with bold colors and a wild mix of contemporary art and modern and vintage furniture. Then, last year, he was approached with a strikingly similar job: same clients, same aesthetic, and, incredibly, the same building. An 1,100-square-foot one-bedroom on a lower floor had come up for sale, and the Londoners had snapped it up. It was to be something of a pied-à-terre for their existing pied-à-terre— a place to host guests, throw parties, and escape from the four kids slowly annexing the apartment above. Because the new space was smaller, a few structural changes were required to match it to the original. Door frames, for instance, were enlarged to play up the drama of the floor-to-ceiling windows. But by and large, says Couturier, “we had the same approach. [The two apartments] are like twins—there’s no stepchild here.”

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