“…he was a great painter and sculptor, but as an architect he was divine, considering that architecture is wholly founded on drawing”

(Bernini on Michelangelo)

Michelangelo (1475-1564) always insisted that architecture was not his profession, but the design of buildings became the principal activity of his long career. He introduced a vein of poetic invention into architecture, arriving at unorthodox solutions above all through drawing, though also through three-dimensional models in clay. The creative processes visible in his designs for sculpture and painting are mirrored in his architectural drawings. He proceeds from small initial freehand sketches (the ‘first thought’), through the working out of spatial and compositional ideas in ground plan and elevation, to the formal design in pen, ink and wash, worked up in detail for demonstration to the patron. Even such ‘finished’ drawings are the starting point for further ideas and elaborations, in a process which resists closure. Michelangelo also communicated with patron and workforce by means of  wooden models, both at reduced scale and one-to-one, full-scale mural drawings of doors and windows, and through metal templates for cornices and bases, cut around full-scale profiles.

Paper was expensive, and Michelangelo was frugal. He drew on every surface, employing letters, poems or household accounts to jot down his ideas. For ambitious drawings he used the largest foglio reale, or stuck several sheets together. To draw, he used the same quill pen and iron-gall ink with which he composed his exceptionally beautiful handwriting. But he also exploited the brilliant effects of red chalk and the subtle expressivity of black chalk. In later life he relied almost exclusively on black chalk for both figural and architectural drawings, combining it with a diluted ink wash for demonstration sheets,  sometimes highlighting (or cancelling earlier ideas) with white lead.

To prepare himself for his first important architectural commission, the façade of San Lorenzo in Florence, Michelangelo copied drawings of ancient buildings from a friend’s model-book, concentrating on eloquent profiles rather than archaeological details. At this stage his architectural language was close to that of Bramante and Raphael in Rome. His frontal and planar approach to design was related to the architectural composition (known at the time as the ‘quadro’ or frame) of large-scale sculptural monuments such as tombs. As his vocabulary became more personal and ambitious, he developed a way of drawing in which he superimposed one idea over another. The process of drawing itself generated unorthodox, composite solutions. He almost always avoided perspective in his drawings, adopting strictly ‘orthogonal’ projection, so that depth can be hard to read unless a ground plan is present. Already in the designs for his Florentine buildings, the New Sacristy and the Laurentian Library at San Lorenzo, we see ideas that were brought to fruition in his Roman architecture, at the Palazzo Farnese, the Capitoline Hill and the Sforza Chapel. The Porta Pia is a summation on giant scale of the layered, palimpsestic designs for doors and windows first made in Florence.

“It will be represented and drawn precisely, which I was unable to do myself because of old age.” (Michelangelo, on his drawing for San Giovanni dei Fiorentini, 1559)

The redesigning of the basilica of St Peter’s and its dome was Michelangelo’s most important architectural achievement, which he regarded as a sacred, almost penitential task. We hear of him in the last years of his life at the age of eighty-six, rising early and spending three hours making drawings for the Porta Pia, before getting on his mule to cross Rome to the building site at St Peter’s. In his late drawings, in endless layers of chalk and wash with constant revisions, his trembling hand mapped out architectural ideas with the force and profundity of his final meditations on the theme of the Crucifixion.