Esther van Deman was important not only as one of the first female Archaeologists, but also for writing the original survey of Roman building methods, materials, and chronology. This paper encapsulates her work into a short form focused specifically on Roman concrete buildings, showing the methodology by which building chronology was set. Even in modern times, this sort of work forms the basis for the dating of Roman buildings. This paper is of use to anyone wishing to develop a more nuanced understanding of how and why Roman buildings are dated as they are and the process by which the dating of material remains are arrived at.