The “digital twin” (DT) of a historical building is a three-dimensional technological replica which is bidirectionally linked to its physical asset, the historical construction. This connection allows to access “in detail” to all the parts of the emblematic building as well as the data captured by the on-site sensors, improving the phases of diagnosis, intervention, and preventive maintenance. Among the different technologies that this approach implements, it is possible to highlight the use of HBIM (Historic Building Information Modeling) methodologies as well as different remote sensing methods for the geometrical modeling. These strategies allow to know the peculiarities of the different construction systems, including the interior of their walls, as well as the interoperability between different simulation engines. The latter includes advance numerical simulations that are able to predict the response of the building under different scenarios such as earthquakes, settlements, or different climate conditions. This chapter will provide a review of technologies for the standardization of the 3D representation of heritage buildings with semantic information (HBIM) and its conversion to DT.
