The Diagonal Grid as a Design Method in the Armenian Medieval Architecture

Armenian architecture has been a subject of serious studies since the beginning of last century. Numerous medieval constructions have been measured, researched and reconstructed. However, there is a major disagreement among the specialists on the existence of a design stage, preceding the actual phase of construction. The absence of actual data and survived projects, as well as the limited historical information on this issue, are the reasons of this disagreement. That is why the historical evidence on the activity of Trdat the architect, provided by the 10th century chronicler Asoghik, is of critical importance. In this historical record the chronicler testifies that Trdat had a preliminary idea on the reconstruction of ruined St. Sofia dome. The information provided on Trdat’s method is of particular interest, as the latter set an example and prepared a model of the future construction. The Cathedral of Ani was erected by the same architect Trdat in 989. The study of the cathedral’s measured materials may shed a light on the issue of existence of preliminary developed drafts with volumetric and spatial solutions of future structures. Here the diagonals drawn by the midpoints of the dome columns are not only the principal lines of the planning, but also a part of a uniform diagonal grid, which underlies the whole plan. The facades fit into a square and all key feature marks are located in horizontal lines, which are set on the peaks of diagonal grid. The slopes of pediment are obtained by connecting the vertices of a smaller grid to each other. The same construction principles were identified as a result of measurement research about Marmashen Cathedral (which was built in the beginning of the 11th century and is attributed to Trdat) and Noravank (this church is considered to be a masterpiece by the architect Momik of the 14th century). The studies have helped to come to the conclusion that the diagonal grid as a design method has been continuously used by Armenian medieval architects throughout centuries. Keywords—diagonal grid; design method; church; plan; facade; square