Rules · Columns · Façades · Proportion
To unify a façade of two or more storeys, run a single order of pilasters or columns through all of them, from the base to the main cornice.
Superimposed orders (Stronger below, lighter above) express each floor; the giant (or colossal) order overrides them and makes the whole building read as one great storey. Alberti had tried it on the front of Sant’Andrea in Mantua, but it was Michelangelo’s palaces on the Capitoline Hill that established it, with Corinthian pilasters two storeys high and a smaller Ionic order carrying the loggia between them. Palladio used giant half-columns on the Loggia del Capitaniato in Vicenza, and giant orders became the standard way to give scale to Baroque churches and Beaux-Arts public buildings.
To find how thick the pier of an arch must be, divide the intrados into three equal parts; draw a line from the springing through the first division, and produce it beyond the springing by its own length. A vertical through the end of that line marks the outer face of the pier.
pier ≈ ¼ span (semicircle) · ≈ 0.23 span (equilateral) · less for a lancet
Front a basilican church with two storeys of the order: the lower as wide as nave and chapels, the upper as wide as the nave alone, joined by scrolls and crowned by a pediment.
Il Gesù (reconstructed): lower ≈ 34 m wide, upper ≈ 20 m; scrolls fill the difference
Build up a façade in layers: let the wall advance in stages towards the central bay, double the pilasters or columns as it advances, and break the entablature forward over every support.
Let the wall of a façade curve in plan (concave, convex, concave) so that the front answers the street, the light and the space within, and the order bends with it.
Proportion every step so that twice its height plus its depth equals the length of a natural pace on the level: two feet, or 24 pouces.
2 r + g = 24 pouces ≈ 65 cm (modern practice: 60–66 cm)
Hold that the beauty of the orders comes from fixed proportions that please by nature, as consonances do in music; where the ancients differ, the differences answer to circumstances such as distance and height.
Cite this page Chris Paton, “The giant order”, The Textbook of Architecture, https://textbookofarchitecture.com/rule/giant-order. Text, drawings and models licensed under CC BY-NC 4.0.