Rules · Light · Columns · Roofs · Plans
In a great columned hall make the columns of the central aisle taller than the rest, and fill the difference in height with stone grilles, so that light enters high up over the side aisles.
The Great Hypostyle Hall at Karnak (c. 1290–1224 BC) has 134 columns: the twelve of the central aisle are about 21 m tall with open papyrus capitals, the other 122 much shorter, with closed buds. The roof over the aisle rests on the tall columns and on a wall of clerestory grilles standing on the architraves of the adjoining rows. The result is the ancestor of every basilica with a clerestory.
Vitruvius knew the type, perhaps from Alexandria: his “Egyptian hall” has columns with a second, smaller order standing over them and windows between the upper columns, so that it resembles a basilica rather than a dining room.
Weight for weight, timber is many times stronger in bending than stone; long spans in trabeated buildings are therefore roofed with timber beams resting on stone walls and columns.
bending strength ÷ density: oak ≈ 70 · limestone ≈ 3 (kPa per kg ⁄ m³)
Orient the principal axis of the monument on the rising or setting of the sun at a solstice, so that the architecture frames it.
Arrange the temple on a single axis (pylon, open court, hypostyle hall, sanctuary) so that at each threshold the floor rises, the roof descends and the light diminishes, until the god’s shrine is reached in darkness.
Model the column on a plant of the Nile (a papyrus stem or bundle, a bundle of lotus, a palm trunk), bound at the neck with five bands, standing on a round base disc and carrying a small square abacus.
Give the columns of the tall, clerestory-lit central aisle open papyrus capitals and those of the lower aisles closed buds.
Cut a shaft with sixteen shallow flutes or facets, give it a square abacus and a low round base: the “proto-Doric” column of the Middle Kingdom rock tombs at Beni Hasan.
Cite this page Chris Paton, “Raise the central aisle and light it from above”, The Textbook of Architecture, https://textbookofarchitecture.com/rule/hypostyle-clerestory. Text, drawings and models licensed under CC BY-NC 4.0.