This research revisits an early space syntax method of ideographic representation which was proposed by Hillier and his colleagues in the 1970s. The method provided an effective way of capturing syntactic relations of enclosure in settlements and houses in its compact format but has not gained the attention it deserves in the field of morphological research. Taking advantage of its power of compressed description, we analyse architectural plans of Korean vernacular houses from the fifteenth to the twentieth century. Tracing the 600-years transformation process by means of a series of ideographic formulae, we investigate the changing patterns of their layout and reveal the genotypical elements shared by a wide variety of housing types. By translating spatial relations to simple linguistic descriptions, the ideographic method enables not only an economic way of representing built environment but also a deductive way of finding generative rules in it.