|Webb and Knapp Tower in 34th Street, NYC. I.M. Pei|
That was back then. Today, if you search Cupples in Google you get files from old legal actions and their last address, a suite in Saint Louis. The nearest website is a link to Enclos, the curtain wall company that lastly absorbed Cupples know-how in curtain walling at the turn of the millenium.
The Sears Tower, once again by SOM and finished in 1973, will deserve a future post only for itself, so no more comments by now.
Many new design, engineering and construction techniques were required for the structures. The exterior skin was 2-million sqf (185,000 m2) of Cupples aluminium curtain wall. It used a then unique and progressive 'pressure equalizing' design which caused wind loads and pressures to be exterted directly upon the building structure rather than the aluminium skin. The steel frame work forming the exterior wall was installed by hoisting in place 3-module opaque prefabricated units, up to 36 ft high and 10 ft wide (11m high x 1m wide). Horizontal aluminium spandrel units - finished with Alcoa Duranodic bronze - were then spliced onto the adjacent unit. All aluminium profiles and sheets were supplied by Alcoa.
|Republic Bank Center, stone curtain wall horizontal details. Above section @ vision glass, below section @ spandrel|
The next - and probably the last - of the great buildings ever to be covered in glass and aluminium by Cupples was not in the US but abroad: the Hong Kong and Shanghai Banking Corporation headquarters in Hong Kong by Norman Foster, finished in 1985. This is a very successful and rare case of project management led by the architect. Foster proposed the Bank to arrange a team of specialists - architects, engineers and contractors - under a sort of design & build contract where architects were the leading partners both during design and construction.
|HSBC headquarters in Hong Kong by Foster, 1985: the most expensive corporate building in the world...|
The merit that this scheme could go well can be mainly attributed to Foster's bold vision, but the other players - Arup and Cupples among them - were also critical. It is worth mentioning here the role of Phil Bonzon, the engineer from Cupples that led the design and construction of the facade throughout the whole process. Bonzon's sketches were unanimously praised by Foster team members as the only way for them to understand the intricacies of what they were jointly designing. Again, the cladding of this building deserves a future dedicated post if not a whole PhD thesis...
|Phil Bonzon's sketches for the HSBC facade design. These details prefigure many industry design features by at least ten years|
Nothing can last forever. Cupples lagged behind during the nineties, due not to a specific reason but probably to a number of them. In my opinion the management team did not anticipate that the one-stop-shop model of vertically integrated production was untenable. Cupples people kept for too long a manufacturing structure that was becoming costly and outdated as years passed. The parent company, H.H. Robertson, was also under a similar stress.
Besides, Cupples was not alone in the market. A later entrant to the curtainwall industry had been operating over the decades under the names of Harmon Contract, Harmon Ltd, and finally Enclos Corp, completing many landmark projects. By the end of the 20th century the two companies, Harmon and Cupples, were operating as sister companies under the same umbrella with Harmon focusing on the domestic US market while Cupples tried to keep pace with international operations. Finally, the two companies became one under the same name, that of Enclos. It can be said that Enclos has inherited and continues Cupples history into the twenty first century.