Visiting Tripyramid Structures


The palette of modernity consists of two colors: sleek, shining grey and the reflected blue of the sky. These are, of course, the hues of steel and glass. As the 21st century marches forward, these materials are being used in ever more daring and eye-catching ways. Soaring crystal roofs with spindly ribs provide interiors with transparent yet sheltering hemispheres; rippling sheets of windowpanes are held aloft by spiders’ webs of cables; sparkling and intricate canopies draw the eye towards the entrance of a shop or office. These types of structures are obviously difficult to build and require a number of different firms and disciplines for their design and construction. One company instrumental in this process is Tripyramid Structures, whose east coast office I visited last month.


A selection of Tripyramid products

Since 1989, Tripyramid has produced linking and supporting steel components with expertise stemming from the founders’ experience working on America’s Cup yachts. Their design of Philadelphia’s Kimmel Performing Arts Center- in which broad glass walls are supported by thin and unobtrusive cables rather than the bulky trusses that were previously used for such designs- cemented their reputation as one of the most cutting-edge component designers in the country, and they have participated in many  major projects ever since. Among their most notable projects are the Tokyo International Forum, the Capitol Building facilities, New York’s new Fulton Center, and the gemlike Apple stores that are now found worldwide.


The Cable-Stayed glass wall of the Kimmel Center

The process of designing a part or system begins with the architect’s general vision of their structure. Some detail-oriented designers provide rough ideas of how they want the components to look or fit in with the structure, but if not it’s up to the Tripyramid drafting team to flesh out the metal. Their tool of choice is the CAD program Solidworks, which has the benefit of allowing load analysis on a model. Once the part design is finalized, it goes to the shop floor, which, in the east coast office, includes multiple machining stations. There are number of lathes, as well as chambers where a cycling variety of tools can attack a chunk of metal from all sides, subtractively forming it into usable hardware. The west coast office works large-scale projects in a forty-foot machining chamber; the Massachusetts branch’s equivalent is fifteen feet long, but still heavily in use. Metals used include steel, aluminum, and titanium- with titanium being vital when working with glass because both expand at the same rate when heated. The products undergo rigorous testing, including tensile stretching, stress measurements, and simulation of vibration, prior to application.

stress img_2270

Top: Stress testing a railing infill. Bottom: a tension tester for cables.

Tripyramid’s area of expertise is somewhat niche, but they are by no means alone among companies in this sense. My eyes were opened during my visit to the complex web of designers, engineers, and specialist firms that are involved in every project. Even the simplest collaboration- between Tripyramid, an architect, and a structural engineer- involves an extraordinary amount of back-and-forth communication to make sure each party’s wishes and specifications are met. For the Grace Farms project in Connecticut, Tripyramid designed thin-strut supports for a roof, six drafts of which had to be sent to architects SANAA before these designers accepted the component. A current tripyramid project, involving a glass elevator, requires cooperation with the principal client, the principal contractor, the architect, a structural engineer, a glass company, an elevator company, and more subcontractors, all at different rungs of the ladder in terms of who is hiring and working closely with who.


The fifteen-foot machine for component manufacture

Over the course of the company’s work, several difficult or unusual challenges have come their way. The developments which were put to use in the Kimmel Center, where glass-supporting nodes stay attached to cables through friction alone, have become a popular feature of construction nationwide. Unusual specifications for a LED-lit mesh balustrade in Hoboken led them to co-manufacture with a company that specialized in farm equipment. For the Nicholas Grimshaw’s new Fulton Center in downtown New York, Tripyramid designed the components for a gargantuan hyperbolic cable-net skylight, which they assembled and experimentally hung outside their building to ensure strength and functionality. Proud trophies of these triumphs- rods and clevises and clips and pucks from built works and glossy posters of major projects- can be found throughout the office.


Testing the Fulton Center reflector net


On-site assembly of the net

At the end of my visit, I asked my guide, John Rappa, what lay in the future for Tripyramid. The firm has several major, high-profile projects in the works, including the Culture Shed at New York’s Hudson Yards complex, but is also always looking forwards. While they consider 3D printing of metal- a topic I have previously explored- a concept currently untenable, they are keeping an eye on developments, as costs quickly add up for projects that use a large number of unique traditional castings. The firm is also considering using smaller-scale, plastic 3D printing as a means of more effectively showcasing component models to clients. Additionally, Rappa was highly optimistic about the rising trend of BIM, Building Information Modeling, in CAD programs. BIM would allow all designers and engineers working on a project to collaborate on a single shared model, hugely streamlining the construction industry. However, BIM’s massive technical requirements mean its application will remain difficult and cumbersome for some time.


More Tripyramid components

Use of 3D printing and BIM remains some years in the future, but in the meantime there is no reason to label Tripyramid as conservative or orthodox. The company has consistently churned out cutting-edge work for decades and has left an indelible mark on many American cities. Further information about their history and projects, as well as contact information, can be found at their website,

Thanks again to Tripyramid Structures Inc. and John Rappa for a truly fascinating tour.


New York City’s famous Apple cube

Total Views: 4048 ,

Add a Comment

Your email address will not be published. Required fields are marked *