San Juan, Puerto Rico
The Selective Restoration of the Capitol Dome of Puerto Rico, completed in 2024, stands as one of the most significant preservation accomplishments in the architectural history of the island.
Located in San Juan, the Capitol building is a Beaux-Arts landmark completed in 1929 and serves as the seat of the Legislative Assembly.
Capitol of Puerto Rico Selective Dome by PQC Architectural Studio LLC., won an 2026 International Architecture Award from The Chicago Athenaeum: Museum of Architecture and Design.
After decades of progressive deterioration caused by the island’s marine environment, seismic activity, water infiltration, corrosion, material fatigue and progressive collapses of decorative terracotta elements, the dome required a comprehensive and technically sophisticated intervention.
PQC initiated the project with an exhaustive diagnostic phase grounded in conservation science and advanced architectural forensics.
The firm performed stone pathology evaluations, material sampling, moisture diagnostics, and 3D digital documentation to capture the true extent of deterioration.
This analytical approach enabled a stone-by-stone assessment of the historic marble envelope and provided the data needed to define a precise restoration plan.
PQC’s strategic methodology honored the original 1920s design intent while integrating technical solutions to address long-term performance challenges inherent to a coastal, seismic region.
A guiding principle throughout the design process was balancing historic authenticity with contemporary resilience. Many of the dome’s marble pieces, mortar beds, and concealed anchorage components had suffered significant degradation.
PQC developed conservation-grade specifications that included the fabrication of replacement stone pieces replicating the geometry, finish, and texture of the originals, as well as the design of mortars engineered to match the chemical and mechanical behavior of early twentieth-century mixtures.
PQC also redesigned and enhanced the dome’s internal support systems to ensure structural longevity.
Working closely with structural engineering partners, the team developed reinforcement strategies that improved seismic capacity, anchorage durability, and resistance to corrosion without altering the dome’s historic aesthetic.
These improvements were fully integrated within the architectural envelope and executed with strict adherence to preservation standards.
The result is a dome that appears visually unchanged while benefiting from an entirely re-engineered, resilient internal framework.
Beyond its technical achievements, the restoration carries deep cultural, civic, and symbolic significance.
As one of Puerto Rico’s most visible monuments and a defining feature of the Old San Juan landscape, the Capitol Dome sits at the heart of the island’s governmental and architectural identity.
The work performed by PQC preserves not only a building, but also the continuity of Puerto Rico’s civic narrative.
The restored dome revitalizes a landmark that hosts public ceremonies, legislative functions, and heritage tourism, reinforcing the Capitol’s role as a living monument and national symbol.
The project has been widely recognized among the world’s most exemplary restoration achievements. It received major distinctions from the College of Engineers and Land Surveyors of Puerto Rico and the American Institute of Architects Puerto Rico Chapter.
Internationally, it earned two major recognitions from the American Concrete Institute, including the prestigious ACI Overall Excellence Award and the First Place Award in the Repair and Restoration category.
Project: Capitol of Puerto Rico Selective Dome Restoration
Architects: PQC Architectural Studio LLC.
Lead Architect: Pablo Quiñones Cordero
Design Team: José Izquierdo, Pedro Medina, and Jorge Santori
General Contractor: Building Preservation Material Technologies (BPMT)
Client: Superintendency of the Capitol of Puerto Rico
Photographers: Pablo Patrignani
