To give a naturalistic effect of mist, our cutting pattern needed to be bespoke and non-repeating rather than linear and mechanical. For laser cutting, it doesn’t matter whether every hole is the same or whether they’re all different. Our challenge was that the panels would have about a quarter of a million perforations, more than we could possibly draw without resorting to standardisation and repetition. We had to find a way of converting our photographic image of mist into a CAD-format cutting pattern that would give the overall composition of a more natural effect, rather than the mechanical one that would have resulted from a simple, linear gradation.
To add another layer into the composition, we drew a geometry of tessellating fan-like shapes as our organisational device, rather than a simple grid. This could be interpreted as the laying pattern of a mosaic, of the granite cobbles in front of the Roman Baths or, perhaps, as stylised cloud or waves (in its Japanese origins it is called seigaiha, meaning ‘blue sea waves’). It adds another visual layer that is only revealed on closer approach to the building or, of course, from the interior. This sense of a subtly shifting appearance according to the viewpoint and light conditions varies and enriches the experience of the building.