During the 1980s and 1990s, Portugal experienced significant urban expansion in the construction of residential buildings on city outskirts, leading to the abandonment and degradation of historic centers and older neighborhoods. Recognizing the cultural and historical significance of these areas, their rehabilitation has become a critical priority. The Building Conservation Assessment Method (MAEC), developed by the National Laboratory of Civil Engineering (LNEC), provides a structured framework for evaluating the conservation status of buildings and guiding decisions between rehabilitation and reconstruction. This study focuses on the development of a digital application designed to support the assessment of the conservation state of facades in historic residential buildings, using criteria defined by the MAEC guidelines. The primary objective of the application is to facilitate informed decision-making, prioritizing comprehensive building rehabilitation over the prevalent practice of reconstructing while preserving only facades. By offering a user-friendly and accessible digital platform, the proposed application aims to standardize and streamline the evaluation process, enhancing the efficiency and reliability of conservation diagnostics. The expected outcomes include the promotion of sustainable rehabilitation practices, the preservation of architectural heritage, and the establishment of a tool that supports policymakers, urban planners, and conservation professionals in their efforts to protect historically significant buildings.