Filippo Brunelleschi – Godfather of Domes

Filippo Brunelleschi is definitely one of the greatest influencers in architecture, and the one who solved the big challenge of finishing the first dome in its style: The famous Florence Cathedral.

Based on sacred geometry and the deepest mathematical research, the dome was completed. The cathedral had been started in a later rejected Gothic style, which was taken back to a traditional Greek inspired dome. So, as Weylin, it was also a Neoclassical. The whole construction took almost 200 years.

The building of such a masonry dome posed many technical problems. Brunelleschi looked to the great dome of the Pantheon in Rome for solutions. The dome of the Pantheon is a single shell of concrete, the formula for which had long since been forgotten. The Pantheon had employed structural centring to support the concrete dome while it cured. This could not be the solution in the case of a dome this size and would put the church out of use. Brunelleschi chose to follow such design and employed a double shell, made of sandstone and marble and he would have to build the dome out of brick, due to its light weight compared to stone and being easier to form, and with nothing under it during construction. To illustrate his proposed structural plan, he constructed a wooden and brick model with the help of Donatello and Nanni di Banco. The model served as a guide for the craftsmen, but was intentionally incomplete, so as to ensure Brunelleschi’s control over the construction.

His solutions were ingenious, such as his use of the catenary arch for support. The spreading problem was solved by a set of four internal horizontal stone and iron chains, serving as barrel hoops, embedded within the inner dome: one at the top, one at the bottom, with the remaining two evenly spaced between them. A fifth chain, made of wood, was placed between the first and second of the stone chains. Since the dome was octagonal rather than round, a simple chain, squeezing the dome like a barrel hoop, would have put all its pressure on the eight corners of the dome. The chains needed to be rigid octagons, stiff enough to hold their shape, so as not to deform the dome as they held it together.

At Weylin we honor two dome style, with our main, closed, masterpiece painted by Peter B. Wight; and our Oculus Dome inspired by the ancient Byzantine and Greek ones in its structure and bull’s eye.