Site size: 5,382 square feet. Project size: 6,997 square feet. Program: A family living in Mexico City asked Jose Juan Rivera Rio and his firm to design a modern house with ample privacy for family and space for guests. Location: The house occupies a narrow walled-in site in a residential section of the city, Lomas de Chapultepec. Solution: The architects, inspired by 1960s modernist architecture, designed a rectilinear house featuring thick, concrete or stone walls and deep overhangs. Lush vegetation outdoors and wood floors and slatted screens inside provide a warm contrast to the textured, board-formed concrete structure. A discreet