VarVac is one small component of a larger renovation project. In this case it was the remodel of the front office of a School of Architecture. The entire space received a new liner strategy that incorporated storage, display, reception, and seating. VarVac forms one wall of this liner, located behind a main reception desk. We conceived of this wall as acoustically heterogeneous. In other words, parts of the wall will absorb sound while other parts will reflect sound. The wall is comprised of vacuum-formed panels with milled perforations that strategically reveal an acoustic backing. Other panels remain solid and reflective.

Our team was asked to participate in the redesign of a small office space - the front office of the school of architecture at the University of Minnesota. As part of the redesign, we were asked to develop a solution to the problem of noise in office. The office is located in the original modernist building (Thorshov and Cerny, 1960). The surfaces are largely cast concrete, brick, and windows made of steel and glass. All of these surfaces are acoustically reflective. The result is a very live space. The acoustic reflectivity combined with a very active student and faculty community resulted in a less than ideal work environment for those staffing the office. We were asked to develop a compelling architectural solution to the problem of noise at the reception desk cheaply and efficiently.

In past research, we have explored vacuum forming as a method for producing low-cost, complex architectural surfaces. The cost of the mold and its inflexibility has prohibited aggregation with difference. So we asked the question: Could a more sophisticated and cost effective mold allow for endless variation in a fabrication process where variation is typically impractical? We set out to solve the problem for our client and in doing, develop a system that would allow us the flexibility to respond to the specifics of acoustic mediation.

Our practice is based on collaborative research. Both partners have backgrounds in traditional practice. We have both left practice and work to develop tools, processes, and prototypes that can exceed those available to architects in the marketplace. We brought an interest in tool making and prototyping to the client and to our work on VarVac. The research positions our design efforts strategically at the front end of the fabrication process (unusual for architects). Our goal is to develop a malleable tool that allows for endless variation in a fabrication process where variation is typically impractical.

Our framed our research on VarVac Wall around the idea that there is tremendous potential in the field of dynamic mold making. Real-time variability in forming fabrication processes sponsors a more careful examination of the relationship between program and material (function and form). The ability to carefully tune that relationship might allow for the exploration of new and novel dialogues, whether comfortable or uncomfortable, efficient or inefficient, compliant or resistant. In addition, our research suggests that variability in the production of architectural components can be achieved as easily and efficiently as repetition and consistency, through the emergence of a type of simply generated complexity within the process.

To answer this question we will describe our process for fabricating the individual components in VarVac wall. Additionally, we have provided a pdf to further describe the process. To make panels that billow out to different degrees with varying sized bumps, we developed a mold comprised of a large frame across which we stretched insulated wires. These wires form an open grid, like a super-sized window screen. Polystyrene sheets are heated and slumped onto this open grid where gravity takes over to form the geometry of the pillows. The further apart we space the wires the deeper the draw of the plastic, which results in a bigger pillow. It is a simple system, which gives us a nearly infinite variety of panel permutations through a basic mold reconfiguration.

Complexity in VarVac lies in the system we developed to digitally predict the geometry of its pillows and iteratively test different panel configurations. To accomplish this we built the wires and frames in Grasshopper. The location of wires on each panel is randomly generated, but wire density is based on an imported gradient image. Where the image is more saturated in magenta, the wires are spaced further apart, where it is less saturated, the wires are spaced more closely (see pdf). The image correlates directly to how we want the wall to perform acoustically. Then, using the Grasshopper plug-in, Kangaroo we slumped a surface over the wires. Interestingly, there was no way to truly predict the shape of the panels in Kangaroo. We intuitively knew what looked right, but in order to precisely tune the digital model, we needed to physically prototype the panels. Then, we could measure their depth under various wire spacing conditions and adjust the settings of the digital model to more accurately predict how the panels would really look.

This back-and-forth working method, between the physical and the digital, as a necessary part of the project’s development, is uniquely pivotal to its success. In addition to helping us accurately predict its appearance, it has allowed us to accurately map tool paths for cutting the pillows on the CNC-mill. To turn the wall’s “hills” into “buttes,” we produced a custom rotary blade for the mill that cuts the panels from the side (x & Y direction) rather than from above (the z direction). Eventually we found that a CNC controlled hot-wire worked best. This frees the tool path from having to be overly precise. The combination of precision in the digital model and allowance for imprecision in the actual cutting process allows us to generate tool paths directly from the Kangaroo / Grasshopper model without physically measuring each panel as it emerges from the vacuum-former. While a subtle streamlining of our production methodology, this has proven to be an invaluable time-saver.

We see VarVac Wall as more than a situated installation. We are interested in what the project represents as a strategy for developing cost effective, material and energy efficient (in terms of production), and formally variable surfaces.

Real-time variability in forming fabrication processes sponsors a more careful examination of the relationship between program and material (function and form). This is not to suggest that a one-to-one relationship is best or desired. However, the ability to carefully tune that relationship might allow for the exploration of new and novel dialogues, whether comfortable or uncomfortable, efficient or inefficient, compliant or resistant. In addition, our research suggests that variability in the production of architectural components can be achieved as easily and efficiently as repetition and consistency. By decoupling monetary economy from formal repetition, many of architecture’s long-standing limitations can be undermined and vigorously challenged.

The bottom line is that our research is not just about the development of new material production technologies. Rather, the systems we have developed set the groundwork for interrogation of more conceptual architectural themes. Moving forward, we hope to foreground an argument that inextricably joins a technically oriented line of research such as ours (flexibility where there previously was none) with larger, weightier issues of timeless and broad importance (like the relationship between program and material). Only with such lofty goals in mind can this type of research resonate with a wider audience and maintain relevance within a larger architectural discourse.