Archaeology of buildings is based on the observation and study of preserved walls, to understand the various phases of construction and renovation that made its history. Characterization of the internal pattern is a part of this work, but it is rarely directly visible. Indeed, plaster or facing covering the walls make the visual observations difficult. In an attempt to provide archaeologists answers, Geophysical and Remote Sensing Units of Inrap is developing new masonry inspection protocols, notably using high-frequency radar.