When Justin Portman bought this place in 2000, he asked his architect, John Cavagnari, to build a “Zen bachelor space.” Hence the outdoor soaking tub and cedar-planked terraces. But the “bachelor” part didn’t last: The next year, Portman married Natalia Vodianova, the face (and body) of Calvin Klein’s underwear ads. Since then, the loft’s edges have been tempered by butterfly collections and soft sofas. This month, Vodianova bore the couple’s third child, and they’ve settled in London. The penthouse sits, awaiting the next seduction.