The analysis of chemical residues trapped in the dirt floors of Structure 1 (below) in conjunction with the distribution of artifacts, revealed that during the Early Postclassic Period (A.D. 900-1150) people in Xaltocan had different rooms for sleeping, cooking, and entertaining guests, just as we do today. For example, I found that Cuarto 7 was used for processing fish, Cuarto 3 was a sleeping area, and Cuarto 8 was a reception area for entertaining guests. Although Structure 1 may look like one large house, it had at least two separate ‘apartments’ occupied by two separate households, divided by the long wall running east-west through the center of the structure. Each apartment had its own hearth, midden, and outdoor patio. Early Postclassic houses were made of adobe bricks with clay foundations and reed roofs.
De Lucia, Kristin, 2013. Domestic Economies and Regional Transition: Household Multicrafting and Lake Exploitation in Pre-Aztec Central Mexico. Journal of Anthropological Archaeology, Vol. 32, pp. 353-367.