An architecture generated by computational rules: forms defined by parameters and scripts, in which every element can vary continuously: twisting towers, flowing curved surfaces and façades of panels each slightly different from the next.
Parametric design means defining a form not by drawing it directly but by writing the rules that generate it, with parameters that can be changed. The idea is old. Gaudí found his forms with hanging models, Frei Otto with soap films, and Luigi Moretti used the word architettura parametrica in the 1940s–60s, but it became general only when the software used to design aircraft, cars and animated films reached architects in the 1990s, followed by scripting tools such as Grasshopper (2007).
The early “blob” architecture of the 1990s explored smooth, free forms; by the 2000s the emphasis shifted to rule-based systems in which structure, skin and pattern are differentiated and correlated. Patrik Schumacher, partner of Zaha Hadid, gave this the name Parametricism in a manifesto of 2008, with explicit rules: avoid rigid platonic forms, simple repetition and collage; make every form malleable; differentiate gradually; correlate the subsystems. The work of Zaha Hadid Architects (the MAXXI in Rome, the Heydar Aliyev Center in Baku) is its best-known example.
Its characteristic devices are the gradient and the field. A tower whose floors each rotate by a small angle (Calatrava’s Turning Torso, Gensler’s Shanghai Tower), a façade whose panels open or close with their distance from an attractor point, a roof whose structure thickens where the loads concentrate: all are one rule applied to many elements. Digital fabrication (CNC cutting, 3D printing, robotic assembly) makes non-identical parts affordable.
Critics accuse parametric architecture of arbitrary formalism and of indifference to cost and context. Its defenders answer that the same tools are used to optimise daylight, structure and energy, and that rule-based design is now simply how complex buildings are made.