In previous blogs, we’ve discussed how we can achieve highly transparent facades in our point-supported structural glass article and expanded upon the topic further when we talked about glass fin wall systems. Tension facades are another sharp looking solution to make the transparency of glass the stand-out feature, thereby further minimizing the visible structure from the inside and outside.
Tension facades use high tensile cables or stainless steel rods to impose the loads of the facade on the main structure. This decreases the amount of solid structural elements visible on the project, therefore increasing the transparency of the facade. The two main types in the industry are tension rod facades and cable net walls.
Many tension rod facades often utilize 1”-2” thick horizontal steel plate beams, that can vary in depth, to brace the system for wind load behind the horizontal joints. These plates beams are combined with vertical stainless steel sag rods/cables to support the dead load of the glass and pick up some of weight of the beam between attachment points at the building columns. The resulting structure helps to spread out the forces put on the building, while keeping the sightlines very clean inside and out. A variation of this facade uses the geometry of vertical stainless steel rod or cable truss structures to provide a unique high-tech aesthetic from the inside, blending the stability of a truss system with the modern look of stainless steel components.
Interior and exterior look at a tension rod facade implemented at the NuSkin Innovation Center in Utah
In addition to tension rod facades, the Pilkington Planar™ systems can also be designed to be cable nets. These systems can use both vertical and horizontal cables or one-way vertical stainless steel tension cables or rods that are pre-tensioned from the boundary structure to act as support for bolted Planar glass panels to be be hung off of. A simplistic way of thinking of this is that of stringing a tennis racket. A surrounding frame is built with cables brought across it and those cables are pulled tight and locked in place. These glass systems, however, impose tens to hundreds of thousands of pounds on the surrounding structure (depending on width of module and unsupported spans), often requiring large steel truss beams at the head and large embeds or steel at the base for tensioning off of. This system when paired with Planar Integral or Intrafix fittings can be supplied without the use of any exterior bolt hardware (as the bolts are concealed with the laminated glass or insulating glass unit, respectively) creating an even cleaner look.
There are multiple ways to implement tension rod facades and cable net systems into your project. From vertical tension rod truss facades like the NYPH Milstein Heart Pavilion entrance, to a tall steel plate beam and sag rod wall at Massachusetts General Hospital, to skylights with horizontal tension trusses and laminated glass fins at Orlando International Airport or a 150 foot tall cable net wall at AOL Time Warner Center in New York City, these diverse point-supported system applications offer a wide array of options for your project.
These complex systems, however, require a high degree of up front design and planning with the project engineers and architects to ensure that adequate perimeter boundary structure is correctly implemented early on in project development. If tension rod facades or cable tension walls sound like the point-supported system that’s right for your project, feel free to contact us.
W&W Glass LLC is a family owned business with a 70-year history in the metal and glass industry, one of the largest metal and structural glass companies in the New York metropolitan area and the largest supplier of structural glass systems in the country. We have over two decades of experience in the design and installation of various building enclosure systems, including stick-built curtain walls, pre-glazed unitized curtain walls, Pilkington Planar™ structural glass facades, and custom metal and glass enclosure systems. We install all of our work with our own dedicated union labor force. W&W is consistently the largest employer of glaziers in the NY metropolitan area.
