Roofing an Early Anasazi Great Kiva: Analysis of an Architectural Model

Abstract

Great kivas played an important role in the social and ritual integration of prehistoric Pueblo societies in the northern Southwest. Early great kivas are found throughout the region, and a partially excavated example from Grass Mesa Village is used to develop an architectural roof design for a Pueblo I great kiva. Based on this design, the required diameters of the primary beams, secondary beams, and roof-support columns are calculated, and the construction costs are estimated using results from replicative building experiments. Based on climate and vegetation reconstructions for the area around Grass Mesa Village, it appears that the necessary materials were available locally. The results indicate that the construction project would require approximately 8,850 person-hours. Based on probabilistic estimates, the population of Grass Mesa Village at the time of great kiva construction (late A.D. 700s) was 38 to 58 households. If 40 households each contributed one laborer for 50 hours per week, the project could have been completed in less than five weeks. Because the Grass Mesa great kiva was the only structure of its kind in the area at that time, a much larger regional population could have participated in construction and completed it even more quickly.