II. Medium

While mosaics and wall paintings remained the preferred means of embellishing buildings in the Byzantine East, the Latin West deployed carved stone by and large.

III. Line

The lines of churches and cathedrals are angular, deploying a theme of reaching to heaven, while the more grotesque sculptures on the friezes make use of more rounded shapes

IV. Space

Some of the most inventive art of the Middle Ages appears in the expansive portals of churches, on the rectangular sides of piers, and on the cramped contours of column capitals.

Color
The bright Byzantium mosaics are a sharp contrast to the more staid stone of the Latin West.

VI. Expressive content, Style and form

Much of the charm of architecture in church building was derived from gargoyles and other carved scenes depicting Biblical motifs. Although designed to enhance worship, the style of individual creations could be playful, even if the overall intent of the work was serious.

Source

The Metropolitan Museum of Art. "Medieval European Sculptors." Museum Website. 2 Jan 2004. http://www.metmuseum.org/toah/hd/arch/hd_arch.htm.