When I was researching structural curtain wall systems, I realized most of them cost at least $200-250 to $300 range depending on the clips, hardware, and glass make-up. I became interested to find the alternative system that would cost within our budget, yet features frameless curtain wall look.
In this case, VS-1 curtain wall system from the Innovation Glass seemed a good fit that cost generally (based on 2014 Feb. inquiry) between $80 and $110/SQFT installed. (depending on wall complexity, accessories, vents, etc.) This is almost half price of the typical structural glass system. Thanks to Franz Safford from Innovation Glass for providing very helpful information about the product.
VS-1 curtain wall system is a vertical blade system without the horizontal mullions. Thus, aesthetically it can accomplish the planar look from the outside like more expensive conventional pin-point connection type (spider or glass fin) system without the sacrifice of cost. The vertical blade mullions in the back of the system can be customized to minimize the visual attention with over 40ft clear spanning.
The best case study would be the Spertus Institute for Jewish Learning and Leadership building on Michigan Ave in Chicago. It was designed by Chicago-based Krueck & Sexton Architects and completed in 2007. The main feature of the building can be the facade with 10 stories high faceted curtain wall system. Typical glass panel size was 4′-4″ x 7′-0″ with custom shaded aluminum mullion spanning 14′ and 21′ on floors. The glass was manufactured by Viracon and installed by Arcadia.
It may look too busy here like the back of Frank Gehry’s typical metal panel facade system, however please note the customized vertical mullion profile was specially designed to accommodate the various multiple angles for the faceted facade system.
Although it requires the vertical mullion blade system in the back of glass panels, I could easily see this as a strong alternative system that is cost effective and offers aesthetically planar flushed uninterrupted look as other conventional pin-point connection structural glass systems.