The project is located on the rooftop of an early 20th-century palace where cultural and festive events are held, in the center of Mexico City. In order to prevent the occasional rains from interrupting the activities organized in the courtyards, the owner of the property was required to cover the three existing patios. Instead of making three independent interventions, the architects generated one single proposal: a continuous roof structure, measuring more than 50 meters in length, connecting the patios in a straight line and generating new covered surfaces in between the patios. The structure consists of 45 lightweight metal trusses, each 1.2 meters apart, dividing the weight evenly over the existing construction and accentuating rhythm and perspective along the roof. The triangular roof section is designed asymmetrically so that one side could incorporate a covered circulation. Light and industrialized synthetic materials such as the PVC deck, polycarbonate sheets or the railings made of nylon nets, seek to reduce the weight of the construction and generate a strong contrast with the materiality of the historic building. Two different types of polycarbonate were used (translucent and transparent), to filter the sunlight, while allowing to see the sky from the courtyards. Additionally, textile screens (borrowed from the agricultural industry) are integrated in specific places to mitigate the solar incidence. The geometric rhythm of the structure is complemented by another series of elements such as the planters that overflow the patios and delimit the new terraces, or the light fixtures that highlight the intervention in the city's skyline. As an alternative to demolishing historic—but often not registered—buildings in Mexico City, this project shows how valuable structures can be re-used and adapted in an intelligent way, when the financing for a full-scale restauration is not (or not yet available). It explores the esthetic quality of the building “as found “—and enhances that experience by contrasting it with a contemporary intervention.