Hold that the beauty of the orders comes from fixed proportions that please by nature, as consonances do in music; where the ancients differ, the differences answer to circumstances such as distance and height.
Fitness and economy
Seek in every building only fitness (solidity, healthiness, convenience) and economy (symmetry, regularity, simplicity); a building that has these will please, and ornament added for its own sake is waste.
Durand wrote for engineers who would build for the state with public money. He argued that architecture had been led astray by imitation (of huts, of bodies, of Rome) and that its true aim was utility. Symmetry and regularity were justified not by beauty but by cost: a symmetrical, regular plan uses fewer different parts and less wall to enclose the same area. The geometry bears him out: a square encloses more space for its perimeter than a long rectangle, and a circle more than a square.
Related rules
Give the flight of steps before a temple an odd number, so that one who starts with the right foot will also set the right foot first on the top.
Judge every building against the first shelter: four trees for columns, branches laid across them for the entablature, and a pitched roof whose end makes the pediment. These three are the essential parts; all else is added.
Let columns stand free, round and upright, carrying a straight entablature directly; do not engage them in walls, replace them with pilasters, or set them on pedestals.
Avoid the ornaments that have no model in the hut: broken or curved pediments, pediments on the long side of a roof, orders piled storey upon storey on a church front, arches carried on columns, and twisted or cabled shafts.
Build every type (temple, museum, college, hospital, barracks) from the same small set of elements, combined about axes parallel, perpendicular or concentric to one another.
Cite this page Chris Paton, “Fitness and economy”, The Textbook of Architecture, https://textbookofarchitecture.com/rule/durand-economy. Text, drawings and models licensed under CC BY-NC 4.0.