|Ph.D Student||Bar-Am Shahal Liora|
|Subject||Constancy and Variability in the Evolution of Basilican Spac|
|Department||Department of Architecture and Town Planning||Supervisors||Professor Emeritus Gilbert Herbert (Deceased)|
|Professor Emeritus Aharon Kashtan (Deceased)|
The basilican space-type is a spatial concept that evolved over twenty centuries. Basilican buildings vary in size, stylistic expression are geographically dispersed and differ in their role and uses. The lack of explicit formulation of the term "basilica" in the literature implies an agreement on its essence. It is hypothesized that these buildings can be identified and grouped according to a set of constant, unchanging spatial features common to all of them, and that the diversity within the group can be accounted for by varying spatial features. The characterization of these “constant” and “varying” traits is the aim of this study.
The methodology used in this study is based on the assumption that a comparison of ratios and proportions in a large number of buildings will make it possible to identify the similarities and differences among them. The variance of a ratio was taken as a measure of the degree of its uniformity. Thus more uniform ratios constitute the constant traits of the basilican corpus, while less uniform ones stand for its varying ones.
108 buildings, from Late Antiquity to the Renaissance, considered as characteristic basilicas of their time and location, were analyzed. These include both civic and ecclesiastical buildings, from various geographical regions in Western Europe. Both quantitative variables (ratios between measured components in plan and section) and qualitative variables (spatial and building components) were analyzed. Ratios were analyzed by period, geography, combined geography and period, and spatial components and elements.
The sizes of the buildings were found to gradually diminish from Late-Antiquity to the Ottonic period, and to gradually increase thereafter, accompanied by an increase in the slenderness (span to height ratios) of the buildings. The average values of the ratios were found to cluster around specific values such as 1/5, 1/4, 1/3, 1/2, 2/3, 3/4, and /2, /2. This suggests the use of established ratios in the process of design and actual construction, and is in accordance with other studies dealing with mediaeval systems of proportion. More uniformity was found in ratios of two measures along the same axis than along two axes. Functional transitions (from civic to ecclesiastical) and stylistic transition (from Romanesque to Gothic) were not found to be accompanied by significant changes in the ratios used.
The findings suggest the coexistence of two operative canons in the design process of basilican buildings: regional, that vary with time and place, and are expressed in those ratios such as slenderness; and universal, manifested in the unvarying ratios.