Located 130 miles from Barcelona in the middle of the western Mediterranean, the island of Menorca is famed for the beauty of its coastline and for being quieter and better preserved than Mallorca and Ibiza, its higher-profile Balearic sisters. Alicia Casals San Miguel and Karl Johan Nyqvist of NOMO Studio have made something of a reputation on the island for a series of vacation retreats they’ve designed there. With this one, nicknamed Stepped House, the Barcelona- and Stockholm-based architects turned the clients’ request for something low-maintenance into a rigorous Miesian exercise in the assemblage of unadorned building blocks.