A catalogue of built forms, using a binary representation

Abstract

A technique is described for the representation of a class of rectangular built forms. Each individual form is produced by applying a series of transformations to a single generic or “archetypal” form, which is designed to take care of the broad constraints, on built space, of close-packing and the requirements for natural light and views. Parts of the archetype which are selected for inclusion in any particular built form are then designated by 1s, and parts which are suppressed by 0s. This makes it possible to assign a unique binary code to each different (undimensioned) built form produced from the archetype. Binary codes corresponding to all legitimate forms may then be arranged in ascending order, to create a comprehensive catalogue. The paper describes such a catalogue comprising forms with up to four courtyards, described by 22-digit binary strings. Metric values may be assigned to the various dimensions of each form, making it a matter of simple arithmetic to compute such attributes as volume, surface area, minimum site area or floor space index. From logical operations on the binary strings it is possible to identify a series of configurational characteristics of the corresponding forms, such as their overall plan shapes, the number of courtyards or the potential for symmetry. The catalogue may thus be searched for built forms fulfilling some set of specifications, for example total floor area, site size and certain desired shape attributes. Worked examples are illustrated from the design of multi-storey office buildings. Possible applications are suggested for this approach, in architectural science and the early strategic stages of architectural design