Casa Batlló, Antoni Gaudí's 1904 renovation of a Barcelona townhouse on the Passeig de Gràcia, has long been recognized as one of the masterworks of Catalan modernism. Yet the building, open to the public since 1995 and a UNESCO World Heritage Site since 2005, has never been experienced as Gaudí intended. Layers of subsequent modification, deterioration of original elements, and the inherent incompleteness of Gaudí's project have meant that visitors experienced a building that was, in significant ways, a shadow of the architect's vision. The completion this year of a decade-long comprehensive restoration, led by the Casa Batlló Foundation in collaboration with a team of architects, conservators, and craftspeople, has finally revealed the building in its full chromatic and spatial complexity.
The restoration project, launched in 2015 and funded through a combination of ticket revenue, private donations, and public grants, aimed to address the accumulated conditions that had compromised the building's character. These included the deterioration of original surfaces—trencadís mosaic, ceramic tile, painted plaster, and carved wood—that had faded, been painted over, or been replaced with inferior modern materials. They also included modifications made after Gaudí's completion, particularly changes to the building's lighting that had eliminated the carefully orchestrated sequence of natural and artificial illumination that Gaudí had designed.
The restoration's approach, developed by a team led by architect Jordi Faulí (who also serves as chief architect of the Sagrada Família restoration), was based on extensive archival research and material analysis. The team worked with a collection of original drawings, photographs, and written descriptions that documented the building's appearance at the time of its 1904 completion, as well as samples of original materials preserved in various archives and private collections.
The most visible intervention involves the restoration of the building's celebrated facade. The trencadís mosaic, the broken tile surfacing that covers the facade's undulating forms, had been repaired repeatedly over the decades using tiles that did not match the originals in color, glaze, or manufacture technique. The restoration team worked with a ceramics workshop in Manises, Valencia, to produce replacement tiles that match the originals in every respect, using techniques and materials consistent with early twentieth-century Catalan ceramic production.
The color palette of the facade, which had faded from its original intensity, was restored through a combination of tile replacement and the careful cleaning of surviving original elements. The restored facade reveals a chromatic complexity that had been lost: the blues and greens of the lower facade, the oranges and pinks of the upper sections, and the whites and creams of the crown combine to create an effect that reads differently throughout the day as light conditions change.
The facade's sculptural elements, including the balcony railings and the principal window frames, were restored to their original condition through the removal of paint layers that had been applied over the decades. The underlying materials—a combination of cast iron, wrought iron, and carved stone—were conserved using techniques appropriate to each material, revealing the surface qualities that Gaudí had specified but that had been hidden for generations.
The building's interior, which had been less comprehensively modified than the facade, received equally careful attention. The main staircase, with its carved wooden banister that suggests the vertebrae of a marine creature, was stripped of accumulated paint and varnish, revealing the original wood surface that Gaudí had specified for its tactile qualities. The walls, with their undulating plaster surfaces tinted with natural pigments, were restored using compatible materials and techniques after analysis of original paint layers.
The most dramatic interior intervention involves the building's central light well, the vertical space that brings daylight to the building's interior floors. Gaudí had designed this well with a gradient of ceramic tile colors—blues at the top, where the tiles are furthest from the windows, to whites at the bottom, where they are closest—to equalize the apparent brightness of the surfaces at different distances from the light source. This gradient, which had been compromised by repairs using non-matching tiles, was restored using tiles produced by the same Manises workshop that produced the facade replacements.
The restoration's most technically innovative element involves the building's lighting, both natural and artificial. Gaudí, who was deeply interested in the quality of light and its architectural possibilities, had designed the building with specific lighting effects that had been lost as technology changed and as maintenance priorities shifted. The restoration team, working with lighting designer Javier Gallego, developed a system that recreates the lighting effects that Gaudí had specified while using contemporary technology that meets current standards of energy efficiency and maintenance.
The artificial lighting system, which uses LED fixtures concealed within the building's fabric, recreates the color temperatures and distribution patterns that Gaudí had specified. The system, controlled by a programmatic system that responds to exterior light conditions, produces different lighting effects at different times of day, creating the sense of temporal variation that Gaudí considered essential to the building's experience.
The restoration's most contested decision involved the building's roof, with its celebrated chimney cluster and dragon-like form. The roof's ceramic surfacing, which had deteriorated significantly, required extensive intervention. The team's approach, which involved the replacement of approximately 35 percent of the original tiles, has been criticized by some preservation advocates who argue that the intervention has compromised the building's authenticity. The team defends the approach as necessary to address conditions that had reached a point where the building's long-term preservation was at risk.
For visitors to the restored Casa Batlló, the experience is fundamentally different from what was possible before the restoration. The building's surfaces, with their original colors and textures, create a visual experience of considerable complexity and beauty. The lighting, with its carefully orchestrated variation, produces effects that reveal the spatial sophistication of Gaudí's design. And the relationship between interior and exterior, which Gaudí had carefully composed but which had been compromised by subsequent modifications, now reads with the clarity that the architect intended.
The Casa Batlló restoration demonstrates the value of comprehensive, patient, and well-resourced intervention in significant historic buildings. The project, which has cost approximately 18 million euros and engaged hundreds of craftspeople, conservators, and technicians, represents an investment in the architectural heritage of Barcelona and in the understanding of Gaudí's work more broadly. The restored building, which will continue to welcome visitors from around the world, offers an experience that has not been possible for over a century—a glimpse of Gaudí's full vision, finally realized.
