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Terms of reference

George Grylls

Architects are adopting the language of modelling. They must make it more than jargon to be effective

The boolean void in action Stephen Holl’s  Ex of In House, Rhinebeck, New York (2015).
The boolean void in action Stephen Holl’s Ex of In House, Rhinebeck, New York (2015). Credit: Iwan Baan

Whisper it quietly, but the language of architecture is changing. New words have started to appear in the mouths of professionals. New words with profound implications.

One of these words is ‘Boolean’. According to one 2016 article, Steven Holl ‘frequently sculpts geometric voids – known as boolean voids – into his buildings, creating unusual facades and internal spaces across more simple base structures’ (Dezeen). Another word is ‘extrude’. MVRDV’s Tianjin library of last year apparently ‘extrudes upwards from the site.’ For your average 3D modeller, such terminology raises no eyebrows and if anything helps to clarify the design processes of MVRDV and Steven Holl; but for the layperson the words ‘boolean’ and ‘extrude’ are completely baffling. ‘Extrude’ is not a computer command that structures their working day but rather a floating piece of abstruse vocabulary, one that disorientates with its faintly familiar Latinate root. Didn’t ‘extrude’ appear somewhere in Edward Lear’s Scroobious Pip? Was ‘boolean’ perhaps in Lewis Carroll’s Jabberwocky?

‘Boolean’ is in fact an adjective used to refer to the branch of algebra pioneered not by Carroll, but by another 19th century English mathematician – the logician George Boole. Boole discovered that variables could be alternately expressed as either true or false, a sort of binary language that underscores the entirety of electronics. Computers work on the premise that the answer to each of their functions will be a one or a zero. Computers therefore speak a sort of Boolean patois.

However, in that Dezeen article on Holl’s house Ex of In, unwittingly or not, the word ‘boolean’ has not been capitalised, implying therefore that the ‘boolean void’ no longer has anything to do with George Boolean. What is being referenced no doubt are the 10 commands in Rhino that govern the union or subtraction of two volumes (and if one were to hazard a more specific guess, the command ‘BooleanDifference’ might come to the fore). In all 10 of the Rhino commands, the word ‘Boolean’ is capitalised, signifying therefore the mathematical language governing the modelling function. But in Dezeen’s description of Holl’s artistic retreat in Rhinebeck the word loses its capitalisation to specifically describe the modelling technique of using one volume to subtract from another.

Rapture or disapprobation?

The words ‘extrusion’ and ‘boolean’ are indicative of the way in which architects are now quite literally speaking the language of 3D modelling. Such literal use of 3D modelling language exposes the extent to which a new conceptual language underpins design. There is no doubt that the last 30 years have seen a dramatic shift in the way architects conceive building, one which has prompted reactions of both rapture and stern disapprobation within the profession. Patrik Schumacher has been at the forefront of embracing the active role of the computer in design, yet the idea of submission to the machine still has a tendency to unnerve. Does the tool control the craftsman or rather the craftsman the tool? Is it a collaboration? Does it even matter?

If we lend Holl the benefit of the doubt, we can say that the use of the word ‘boolean’ comes across as an active embrace of technology. And for those who can picture a red extrusion flickering with all the glitchy excitement of an imminent subtraction, the link between the word ‘boolean’ and the signified process is much clearer than the vague denomination of ‘geometric void.’ Holl’s firm leaps headfirst into the language of 3D modelling, and thereby can be said to carve itself a niche in the new literature of computer-based design.

The boolean void in action Stephen Holl’s  Ex of In House, Rhinebeck, New York (2015).
The boolean void in action Stephen Holl’s Ex of In House, Rhinebeck, New York (2015). Credit: Iwan Baan

Does the tool control the craftsman or the craftsman the tool? Is it a collaboration? Does it even matter?

But there seems little clarity in terms of which commands are widely acceptable. Take for example the text released by Zaha Hadid Architects for the opening of its new Morpheus Hotel in Macau – an enormous cobweb-covered cube warped by the omission of a few central organs. The word ‘extrusion’ is used three times to explain the initial design process of creating the solid. Yet the firm is too reticent to use further modelling terminology: ‘This block was then ‘carved’ with voids.’ All the accompanying vocabulary that Holl used to articulate the parti of the Ex of In is intact, but somehow the word ‘boolean’ itself, the very command that has enabled the whole process, has been dropped by ZHA.

While the word ‘boolean’ is still in linguistic limbo, it seems that the word ‘extrusion’ has now reached a critical point of usage whereby its etymology no longer has any bearing on what it means in the architectural profession. Originally it referred to the mechanical process of squeezing a viscous liquid through a die to create a rod with a certain profile. Now it the creation of a solid from a closed line (or ‘curve’ to use the right modelling term). But the ‘extrusion’ process of the 19th century was originally called ‘squirting’, so the word’s meaning has never been static. And when architects are faced with the image of an operation on their computer screen day in day out, and they have been provided with a word to describe that specific operation, it is little wonder that the language of 3D modelling is now translated into their depictions of the everyday world.

  • Boolean difference: A 3D object (blue) is used to subtract from the volume of another 3D object.
    Boolean difference: A 3D object (blue) is used to subtract from the volume of another 3D object.
  • The resulting boolean void.
    The resulting boolean void.
  • The 2D profile of a closed line or ‘curve’ is extruded to make a 3D object or extrusion
    The 2D profile of a closed line or ‘curve’ is extruded to make a 3D object or extrusion
  • The 2D profile of a closed line or ‘curve’ is extruded to make a 3D object or extrusion
    The 2D profile of a closed line or ‘curve’ is extruded to make a 3D object or extrusion

Who are you talking to?

Who though is the intended audience of this vocabulary? Fellow professionals, clients or the general public? If it is fellow members of the architectural profession, then undoubtedly the international language of 3D modelling is appropriate, because the insights into Holl, MVRDV and Hadid’s massing techniques are crystal clear to anyone with even a few hours of experience designing on a computer. One might argue as well that few outside the profession would be interested in the early stages of design that these words describe. Perhaps so. Perhaps the wider world is only concerned with architecture’s implementation and effect. But it is at least worth being conscious of the fact that the new language is so specialised as to be exclusive, and so when speaking to clients and the broader public, ‘extrusions’ and ‘boolean voids’ are just going to extract blank stares.

Every profession has a unique vocabulary that can appear baffling to the outsider. Architecture has always used words like ‘spandrel’ and ‘joist’ that are unlikely to appear in pub conversations with solicitor friends and accountant acquaintances. In the past these specialist words have tended to refer to esoteric parts of buildings, that few other than architects, builders and engineers would even know exist. The fact that the new terms describe the processes of design rather than what is actually built speaks to the conceptual hold that 3D modelling has on the profession.

In the context of greater architectural history, ours is a nascent period within the development of the conceptual language of 3D modelling. For 3D modelling programs are exactly that – languages. Each program belongs to a family, whereby fluency in one helps secure fluency in another. Italian feels simple after Spanish because they are both Romance languages; Revit follows on from Autocad because they are both Autodesk products. And like languages, these programs are quite clearly conditioning the way in which architects are expressing themselves, with both words and designs. This should not necessarily cause consternation. The natural rhythms of the English language have pushed English authors to err towards iambic pentameter, the French language settled on the alexandrine. Those who are conscious of the language they are speaking will have the ability to manipulate it into literature; those who do not will inevitably sink into platitudes.


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