In this last weeks post, (https://arch5541.wordpress.com/2012/11/10/beast-part-1/) we started looking at the Vakko Fashion Center by Rex architects through the lens of disruptive innovation. That first post took a look at the steel structure of the building’s interior, and determined that while the steel structure was certainly destructive, its innovation was arguable, and possibly detrimental. This week, however, I want to move to the exterior of the building to look at one of the most inspiring material innovations I’ve come across this semester: slumped glazing.
As discussed in the previous post, this building was constructed primarily over a pre-existing concrete structure. This concrete structure had been designed for a hotel that was never completed, and had not been detailed in a way that most architects would find visually appealing. The edges of the floor slabs were thick and heavy looking, due largely to the embedded concrete beams. This impossibly obvious structure made it difficult for Rex to develop a facade that would allow the structure to “disappear” as the clients desired.
To lighten the visual effect of the facade and structure, Rex sought to minimise it visually and physically. Ideally, they were interested in spanning the entire floor with a single piece of glass, without the aid of mullions. Given that facades have to be designed to withstand significant loads from winds, and also in this case seismic activity, that poses a significant challenge.
The relatively thin panes that are traditionally used in glass facades would deflect significantly beyond what is structurally allowable. Usually when a pane of glass has to span a large distance, it would be supported on either side by a steel or aluminum mullion, but that would destroy the visual clarity Rex was hoping to achieve. Another alternative would be to use very thick glass panels with multiple layers of lamination, giving each pane the thickness and rigidity needed to resist horizontal loading, but would significantly increase weight, cost, and material usage.
Instead, Rex sought to develop a more specific and elegant solution, that would address each of these issues: It would use no more glass than a conventional dual-pane solution, it would span the entire distance from floor to floor, and it wouldn’t require mullions to resist deflection. After much research and experimentation, the key to meeting all of these needs turned out to be deceptively simple: slumped glass.
By heating a pane of glass in a specialized kiln-like mold, they were able to cause certain areas of the pane to physically droop, giving the glass a structural dimension. Being considerate about the shape of the slumped zone, they were able to develop a form that was not only structural, but aesthetically pleasing as well.
With the entire facade populated with these panels, the effect is striking. The lack of structural support between levels is striking, and the slumped “X” in every pane, far from being distracting, actually gives the glass a juicy dimensionality that is essentially unheard of in contemporary architecture.
In retrospect, this solution seems simple, and almost obvious. Why should glass not take on structural responsibility? With concerns about sustainability high and rising, why should we throw more material at a problem when there a solution that uses less, and is more beautiful to boot?
This is the kind of disruptive innovation in materiality that architecture desperately needs. The kind of innovation that does more with less, and makes it look good.
Now who’s going to let me use their kiln.
Material Strategies 