Planning and proportions in the domed octagonal churches of Late Antiquity

An examination of basic principles in the design of domed octagonal churches from the period, show the prevalent use of round numbers divisible by ten in the measurements of the diameters of such churches. A second finding is that simple proportional schemes were used in the dimensions of the ground plans and vertical elements of these buildings. Particular reference is given to the churches of SS. Sergius and Bacchus in Istanbul and San Vitale in Ravenna