This work culminates the different stages of the Alcorta headquarters of the Torcuato Di Tella University developed since 2009 by RDR arquitectos. It consists of two new levels that finish the building, built with a metal structure and glazed enclosures that rest on the pre-existing roof of the previously remodeled building, fully operational. The fourth floor houses a restaurant, offices and classrooms, and the fifth floor is a large 2,000 m2 garden roof covering the entire length of the plant. This new green space allows the University to expand its recreational areas and enjoy the open views towards the river and the city, attracting students to a new meeting place. The terrace was conceived as a large park capable of housing both leisure and gastronomic venues as open-air auditoriums and sectors for academic and sports activities. The large folds of the roof enrich the route and generate situations of formal and informal auditoriums in the open. These folds, in turn, allow three large classrooms to be housed in the lower floor, conferring the height according to their dimensions. The courtyards bring light to the lower levels and contain the stairs to the terrace from the fourth floor hall. This stage required a material strategy capable of building an additional level on a densely populated building without interrupting its activities. The project took on this challenge not only by including in this instance materials such as metallic primary structures and gypsum rock ceilings and partition walls that allowed an almost exclusively dry work, but also to extend and complete the overhead light inlets and the vertical circulations forming patios through in a delicate staggering of tasks that always kept properly isolated hydrophobic, acoustically and thermally to the spaces of use in the lower levels. Finally, this new architecture emerges in the garden terrace with a palette of natural materials, assembled and light, of evident contrast with the monolithic, neutral and tectonic technology of the concrete and the masonry of the pre-existing building.