The Arribeños building is located in Nuñez, an area of medium density near the north border of Buenos Aires. Because of the tight condition of the site, the construction was organized in two blocks. The first is removed from de ground and unifies the sidewalk with de circulation patio. Despite the scarce dimension, the building encompass four types of units that are simetrically duplicated. They have all been configured with a certain degree of ambiguity allowing them to be used as housing or offices. Each of the project´s decisions intend to take advantage of the high level of vagueness of the program; the building presents itself as a place open to multiple appropriations.