Office Building on Diagonal

This 9-storey building (ground floor + 8 upper floors), constructed in 1943, retains to some extent the compositional aesthetics of the façade and the structural system of the buildings built in the Eixample district of Barcelona before the Civil War. The façade has a stony appearance with regularity and order in the arrangement of the openings, few decorative motifs—typical of the post-war period—and ceramic brick walls as vertical structural elements. It is a typical building from a transitional period between two very prosperous eras: Modernisme, where decorative elements were highly valued, and Modernity, where craftsmanship was abandoned and industrialized construction elements were introduced. The building faces three different streets and is located at the end of a “block” with a pointed end, allowing natural light to enter practically every room. Interior rooms are always connected to one of the lighting and ventilation courtyards, ensuring they also benefit from good natural light depending on the floor height. These interior courtyards also facilitate good cross-ventilation.

The project addresses the developer’s desire to repurpose the building from residential use to office space, which implies adapting every part of the building to its new function. Contrary to the current demand for open and versatile office spaces, the Diagonal 598 building retains, to some extent, the distribution typical of residential buildings where the floor plan consists of separate rooms. This is true to some extent because much of the partitioning in the bay between the façade and the first ring of load-bearing walls (parallel to the façade) has been removed to create an open perimeter suitable for arranging large work groups. However, the innermost part of the floor plan, which is highly influenced by the building’s geometry and the layout of the interior courtyards, retains the original residential layout.

The design solution focuses on attracting businesses to a central area of Barcelona, especially at a time when offices were moving to more peripheral areas where new buildings could offer open and versatile spaces. The client recognized that many offices preferred central city locations, and while many Eixample buildings are occupied by offices, they often lack the facilities that a comprehensive renovation could provide.

Urban planning constraints required us to consider that the regulations applicable to a change in the building’s primary use are nearly identical to those for newly constructed buildings, which are very restrictive. Therefore, a meticulous effort was needed at both the project and execution levels to comply with all these regulations without distorting the existing valuable elements. The plot faced north, and the rooms open onto a large communal space.

What stands out in this project is the skill in preserving and highlighting the valuable architectural elements from the building’s construction period—such as the free heights, the cornices on the ceilings, the wooden joinery on the façades, and the dimensions of the passageways between rooms according to the original layout—while integrating more contemporary architectural and decorative solutions that add warmth to the space. The goal is to create office spaces while maintaining the comfort “feeling” of residential space. To achieve this, wood is introduced into the vertical walls, both in veneered panels and in a more transparent format with wooden slats on glass enclosures in the form of lattices. Depending on the case, either solution is used, but it is the lattice that provides greater visual connectivity between the different rooms, enhancing the sense of space. One of the main objectives was to make the confined corridor/distributor “disappear” visually, integrating it into the spaces it accessed. Another noteworthy aspect is the framing of the passage openings in the load-bearing walls with a steel sheet, which serves a dual purpose: highlighting the transition between adjoining spaces with very different uses and reinforcing the structure of the solid brick walls, which are only 15 cm thick, around the openings. Two types of flooring are used according to the function of each space: a vinyl flooring with better acoustic performance in work areas and wooden flooring in circulation areas, harmonizing with the wall finishes.