Intercolumniation

Illustration from The Four Books of Architecture by Andrea Palladio, translation by Thomas Ware published in London, 1738

In architecture, intercolumniation is the spacing between columns in a colonnade, as measured at the bottom of their shafts. In classical, Renaissance, and Baroque architecture, intercolumniation was determined by a system devised by the first-century BC Roman architect Vitruvius. Vitruvius compiled standard intercolumniations for the three classical Greek orders, expressed in terms of the column diameter, twice the Vitruvian module, and he warned that when columns are placed three column-diameters or more apart, stone architraves break.

Standard intercolumniations

The standard intercolumniations are:

Pycnostyle 

One and a half diameters

Systyle 

Two diameters

Eustyle 

Two and a quarter diameters, considered by Vitruvius to be the best proportion

Diastyle 

Three diameters

Araeostyle 

Four or more diameters, requiring a wooden architrave rather than one of stone

Araeosystyle 

Alternating araeostyle and systyle

See also

• List of architecture topics
• Architectural glossary