Duomo

  

•Largest dome constructed since the Roman Pantheon

•No higher dome had ever been built

•Designed by Brunelleschi, exact time unknown

•Construction began in 1420 and was completed in 1436

•Temporary octagonal oculus until the lantern could be completed, Brunelleschi died before the lantern was begun

•Masons worked from movable scaffolding supported by recently completed sections of the dome

•Constructed without “centering” or a great quantity of wood

•Brunelleschi invented the “Great Hoist”

•Traditionally masons had to carry the building materials up on their shoulders

•Mathematical order, dome is exactly half as wide as it is tall (approx. 138’x 276’)

•Constructed using inner and outer shells

•Made the dome lighter

•Created a protective barrier

•Eight segments, divided by external ribs, contained two hidden ribs each joined by short horizontal ribs

•Outer surface covered in roof tiles

•Inside of the ceiling was frescoed in the 16th century

•Outward thrust partly constrained by a series of encircling “chains” hidden in the structure

•Four stone, One wood

•Held together by iron links

•Lower levels of the dome are constructed in stone

•Upper levels made of brick

•Lighter

•Laid in a herringbone pattern for strength