Architectural Retrofit and Multidisciplinary HVAC Modernization with BIM Methodology: A Study of the Carlos Tortelly Municipal Hospital

The modernization of existing public hospitals requires an integrated approach capable of addressing architectural constraints, outdated engineering systems, and evolving regulatory requirements for indoor air quality, energy efficiency, and operational safety. In Brazil, a significant portion of healthcare facilities built in the late twentieth century present structural and technical limitations that hinder compliance with current ventilation and air treatment standards, particularly after the publication of ABNT NBR 7256:2022. This paper analyzes the architectural retrofit and multidisciplinary engineering modernization of the Carlos Tortelly Municipal Hospital, a medium-sized public hospital inaugurated in 1982 in Niterói, Brazil, with emphasis on the redesign of HVAC systems. The study examines the adoption of Building Information Modeling (BIM) as a methodological framework to support the development of architectural, structural, electrical, hydrosanitary, HVAC, and hospital special systems projects, in accordance with both technical standards and public procurement regulations that encourage BIM use in engineering services. The methodology is based on on-site technical inspections, analysis of existing systems, review of regulatory requirements, and the development of multidisciplinary design workflows. A comparative assessment between traditional sequential design processes and BIM-assisted workflows is presented, highlighting differences in information flow, discipline integration, and project deliverables during the design phase. The proposed BIM-based approach enables a more consistent and compatible engineering project delivery, reducing uncertainties associated with fragmented documentation commonly found in conventional methods. The results indicate that BIM contributes to improved design coherence, enhanced decision-making during HVAC system modernization, and greater alignment between architectural retrofit strategies and engineering solutions. The study reinforces the relevance of BIM as a strategic tool for hospital modernization projects in hot and humid climates, supporting regulatory compliance, technical reliability, and long-term sustainability in public healthcare facilities.