Apartment building in a small plot in Santa Fe City, an extremely flat with a very hot weather city. Northeast corner, at the intersection of Maipú and Urquiza streets. The whole building stands on the south and west party walls, freeing the corner and creating an entrance area for pedestrians and vehicles as well. It is unusual in this line of ventures for common-use spaces to be considered quantifiable in terms of money, thus the attempt to reduce those spaces to the minimum allowed by regulation. By the logics of real estate business, private space always prevails. We are interested in structuring the building around the common-use space, as it establishes an ascending path of multiple configurations that we consider to be its central character. Commencing from the entrance area, we encounter three levels with ample hallways and internal stairs. On the fourth floor there is a public terrace and, on the same level, emerging from the block of apartments, we find open stairs leading to the seven remaining floors. The whole route relates in different manners with its immediate environment. The presence of a small square as entrance area minimizes the impact of a tall building in a low-housing neighborhood. The open hallways allow visual contact in both directions –inwards and outwards, as a sign of empathy to the environment, a visual dialogue that permits all housing units to interact with it. A double wall becomes the architectural envelope. Its exterior face consists of pre-molded concrete lintel-type bricks layered in a rotated way. This succession of small sized parasols creates a self-shading surface that casts shadow upon itself during summer, but lets sunlight impact during winter. The system is completed by an internal 15 centimeter thick wall made of cellular concrete bricks. The supporting structure consists of a system of voided slabs that allows both the ceilings and the floors to remain exposed without any need for cladding. This voided-slabs system considerably reduces the amount of necessary concrete, as well as having a superior thermal performance compared to the traditional solid slab.