July 20, 2008. On August 1 the SCI-Arc Gallery will open Voussoir Cloud, a site-specific architectural installation by San Francisco-based studio IwamotoScott who worked engineering firm Buro Happold (and SCI-Arc students) to design and build a compressed vault system using a featherweight sheet material. Voussiors, wedge-shaped elements that form an arch, were created by folding paper-thin wood laminate along curved seams whose surface tension then maintains their form. The shape of the structure as a whole is determined by each of its parts and their relationship to the gallery walls. Lisa Iwamoto explains how the construction works. www.sciarc.edu, www.iwamotoscott.com, www.burohappold.com How does the installation “confuse” material and structure?
Voussoirs are typically heavy masonry blocks shaped like wedges so that they bear on each other in order to stand. What we are doing is using an ultra-light material, and creating voussoirs (what we are calling ‘petals’) to act structurally like a masonry block. So the “confusion” is really about redefining this age-old construction technique using new materials enabled by digital processes. Our petals are made by folding along laser-scored curved seams. Each petal is then wedge-shaped in three dimensions and acts compressively when packed together, even though they are super lightweight and not solid.
How did beginning with the material alter the relationship of the digital model to the physical result? How closely will the digital model match the final construction?
By beginning with the material operation of folding, using small handmade models to test geometric relationships of bending along a curved seam, the design and construction process that followed focused on calibrating the relationship of digital model to physical corollary through iterative empirical testing. There are four cell types in Voussoir Cloud with zero, one, two, or three curved edges. Each cell behaves in a slightly different manner based on its size, edge conditions and position relative to the overall form. We developed a RhinoScript to automate digitally making the petal.
Digital models and material constructions are never the same. In this case, they will be extremely close, but the design process wasn’t about making a digital model first and then figuring out how to build it, so the closeness is more about how we could digitally approximate as best we could a material condition. The design process that resulted ended up being highly mathematical and really about geometry to understand how folding along a curve affects each petal and then the overall form. I guess we’ll have to wait until we’re finished to really understand how close it will be to what we modeled…
How does an exercise like this installation add to your actual architecture practice? What have you learned or tested? This has definitely been a learning experience. First, it was a great collaboration with the engineers at Buro Happold who really added to the design conversation. They were instrumental in shaping the design using form-finding software. The process of beginning with a material property and working towards an overall design is something we have worked with before (In-Out Curtain, REEF), but not to this extent, nor with the help of inventive engineers. In terms of adding to our architectural practice, it is an opportunity to test ideas at the one-to-one scale and evolve our process of calibrating material, digital and constructive relationships.