A Problem in Perception: Living in Trapezoidal Spaces

Abstract

In journals devoted to architecture one comes more and more often across plans referring to spaces with vanishing, non-parallel, and split walls and other spaces—banana-shaped or perhaps trapezoidal. With respect to these last ones, I shall refrain from discussing the advantages or drawbacks of such solutions, but shall deal with a real problem inherent in them. Such plans are not new. Trapezoidal rooms can be found in circular or outward radiating designs. A prime example is Maison de la Radio in Paris. There the rooms with non-parallel walls are all parts of a circular annulus. People working in such spaces complain of discomfort they cannot identify. I shall try to put forward an explanation. The discussion will be extended to other, larger trapezoidal spaces—the Modern Art Museum in Frankfurt—and open spaces—Piazza del Campidoglio and Piazza San Pietro in Rome—so as to analyse the consequences of the strange effects of counterperspective.