In 2003, UNESCO, with the Convention for the Safeguarding of Intangible Cultural Heritage (ICH), recognized the acoustic characteristics of a cultural heritage building as qualities to be safeguarded. After this milestone, multiple researchers have investigated methods and tools to evaluate, understand, characterize and store the acoustic intangible information. This paper illustrates an experimental and numerical approach useful to accurately measure the acoustic fingerprint of a cultural heritage building; the unique identification of this fingerprint opens the way to a legal protection of the intangible heritage of the sound response of the building. The proposed approach allows to define a forensic process to legally preserve the uniqueness of the acoustic fingerprint of a building. The proposed procedure involves acoustic software that use ray tracing algorithms to simulate the sound propagation; in order to calibrate the numerical models with respect to the experimental measurements, they were used genetics algorithms that allowed to precisely calibrate the absorption coefficients of the building’s materials. This paper aims to investigates the pros and cons of using such techniques and algorithms in intangible cultural heritage acoustic’s preservation and digitization by analyzing its applications and results on case studies.