Architecture of Basilica San Lorenzo by Filippo Brunelleschi

The Architecture of Basilica San Lorenzo

The Basilica San Lorenzo was built during the Quattrocento by the architect Filippo Brunelleschi, with construction conducted between 1422 and 1470. It is inspired by the Church of the Holy Cross (Gothic). The structure is divided into three naves and lateral chapels. In the middle of the transept is a cupola, which is surrounded by chapels. Opposite the middle of the transept is the main chapel.

Geometric and Mathematical Design

Its plan is a Latin cross with three naves and side chapels, forming a basilica that is almost extremely longitudinal. In the transept, which has little development, he set a dome with a lantern. The space was mathematically and geometrically modulated by the circle inscribed in a square, which served as a measure of the proportions provided with reference to the human figure.

Classical Architectural Elements

Very harmonious architectural elements were used, citing the classical world through the influence of the early Christian basilicas. Examples include:

• The coffered ceiling of the square nave.
• The continuous entablature.
• Rich Corinthian capitals on monolithic columns in the central nave and pilasters on the sidelines.

Brunelleschi used a peculiar architectural rhythm in the central nave, which began as a support column, followed by a piece of entablature decorated on the compound capital and a ribbed arch above it. Ribbed vaults were used in the aisles. The architect played well with the alternation of color to achieve the proper bichromy traditional to Florentine architecture.

Proportions and Modular Construction

The module is the central square that inscribes the dome and is the same as that of the central chapel. Each section of the nave is half of the module, and each module is a fourth installment of the aisle. In height, the protagonist is the column, and the height of the nave is twice its width. In relation to the side, the width and height are equal. The ratio of height between the arches that communicate the aisle with the side chapels has a ratio of 5/3.

Lighting and Perspective

The light comes from windows. The vaults in the aisle and the oculi cause light to appear more tenuous, while the chapels remain dark. In conclusion, the light accentuates the gradation perspective. The coffered ceiling is inspired by the Pantheon, but there are also many other classic elements such as pilasters and arches. It also utilizes the signature Florentine bichromy.