The offices take up the entire top floor of a building intended for offices, with a trapezoidal plan and three façades built on the basis of a fiber cement sill, while the rest is made entirely of glass. The structure is based on metal portals. The office program to be installed on that free floor consisted of a reception, a secretary, a meeting room, a visiting room, two offices intended for technicians, an office for an administrator, a library, a draftsman's room and health services for employees and the public. An air conditioning system had to be installed for all the rooms for the summer. In the whole distribution, the existing façade was an important condition, which due to the type and dimensions of the openings, only normally allowed and in a façade perimeter of 40 metres the delivery of dividing partitions in 8 fixed points. Another condition was the pillars of the structure, which, due to their situation in the plan, made it difficult to build partitions precisely at those points where deliveries with the external enclosure were easier. The third condition was to obtain some natural lighting even for the spaces that remained inside and did not receive direct light from the outside. Using a special profile to solve the delivery of the partitions with the façade carpentry, the possible delivery points were increased; and by retracting the dividing walls forming angled windows in each displacement, it was possible to separate the structure of the partitions and give some natural lighting even to the reception, which is the innermost space of the offices. To visually isolate the offices from the outside, protect them from the summer sun, and make the installation of air conditioning as economical as possible, the entire façade has been protected with "American" type windows of white plastic, which separated in their lower part from the face of the façade, create an air chamber between the shutters and the façade, very favourable to avoid a higher heat transmission. To allow the passage of the air conditioning conductors, the false ceiling of the rooms that ventilate directly to the outside have been placed at a higher level than the rest, and between both levels the grilles of air expulsion have been placed. All the rooms in the program are closed spaces except the secretariat, which is separated from the outside only by a counter and a wardrobe hanging from the upper floor and which visually isolates both environments. All the doors, except for the sanitary ones, are of acid-treated glass to give greater illumination to the interior rooms while preserving privacy. In the partitions and during their construction, drilled metal profiles were placed that serve as supports for most of the office furniture.