From Philly Brownstoner, an article on historical construction methods: "The construction of a rowhouse began with a surveyor, who measured and marked the boundaries of a property. A cellar was then excavated and the stone foundation walls laid by masons. Carpenters then laid floor joists for the first floor, embedding the ends into the foundation. Scaffold boards laid across the joists were used for work platforms while bricklayers built up the façade and party walls to floor of the second level, roughing in lintels for windows and doors. Carpenters then roughed in the structure of the partitions with wood planks or stud framing, fastening them by nails to the heavy framing joists and beams of the building. Lath was then nailed to the substructure, over which a brown coat of plaster was applied by plasterers. The structure and design of Philadelphia’s early vernacular buildings were essentially carried out by contractors and artisans without the direction of an architect." Full article here.