In the context of our national and South American reality, with limited public investment resources, and in a global context of climate emergency that demands an urgent change in the use of resources, buildings for public use and destination must be able to reconvert and constantly adapt to the changes that society demands and promotes, becoming opportunities to rethink the way they relate to the city and its inhabitants.

This is the case of the Rancagua Campus Building project of the Universidad de O'Higgins, which is based on the challenge of reconverting and resignifying the building of the old Rancagua Hospital, with a strong imprint of sanitary architecture: functional, heretical and segmented, to transform it into the foundational headquarters of the recently created regional university, with an image that reflects the values of a contemporary public education: flexible, stimulating and inclusive, open to the community and the public space of the Alameda Bernardo O'Higgins, a few blocks from the Plaza de Armas in Rancagua.

The image of the old hospital, which operated for more than 60 years in this building, is strongly rooted in the collective memory of the city, with its 6-story volume and large half-open windows, gray and blue mosaic exterior cladding and its central location with side access, in a complex surrounded by walls and railings that do not allow the building to have a direct relationship with the avenue. Inside, the enclosures with large windows and high ceilings are not perceived from the longitudinal corridor that runs along all floors dividing the north and south fronts of the building, between which a strong contrast is generated: warm north enclosures and cold south enclosures, separated by a dark and very long circulation axis, which does not invite to walk through.

Six intervention strategies are defined, hierarchized by a tight budget but demanding in compliance with environmental comfort standards, for the transformation of the building:

1. Build a covered atrium on an urban scale:
Demolish the perimeter walls and fences, generating a large public plaza that projects the image of the new University on the Alameda, transforming the old south courtyard into a covered atrium of urban scale, a meeting and cultural representation plaza that opens its doors to the city and through which all users can access the Extension Hall and, from there, the public use programs on the second floor of the building (auditoriums, classrooms and casino), as well as the Library, which takes up the entire second floor, abutting the double-height atrium.

2. Recovery of the old hall:
The hall of the old hospital, which was completely fragmented by a series of non-structural divisions, is completely liberated, recovering its spatiality of great height, rescuing the columns with yellow mosaic cladding as the only structural elements and the large window open to the south courtyard, which becomes the natural space of access, central and democratic, from the new covered atrium.

3. Permeate the interior:
Partial perforations and demolitions of slabs and walls are projected to spatially integrate all levels of the building in a new system of stairs and halls that run diagonally through it, stimulating the visual and physical interaction of the community in its different levels.
This diagonal perforation was arranged to the north of the building, seeking to permeate the natural lighting and solar radiation towards the center of the floor plan, thus reducing the energy demand for heating and balancing thermal comfort in a passive way.

4. Hierarchizing the program:
The distribution of the architectural program was studied according to the flow of users. Thus, the rooms with the heaviest use were located on the second floor, around the cultural extension hall, and on the second floor, which is used as the Central Library, placing classrooms, study rooms and offices on the upper floors and concentrating the laboratories, which require a greater relationship with loading and unloading areas, on the base floor of the building.

5. Flexibility of use:
Due to the good structural quality of the pre-existing rough work, its rigorous modulation of 8x8mts and a height of 3.6mts between floors, the interventions did not require major structural reinforcements, being mostly light, which allowed optimizing the use of the existing large enclosures and generating flexible, unitizable and adaptable spaces over time.

6. Building in stages:
The intervention of the building was to be programmed in stages to be executed over a period of 3 years, in a staggered manner and allowing the use of the building from the first moment.