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LINEAGE OF PIONEERS

The direct lineage of Enclos dates to the beginning of curtainwall as a building form in the mid-20th century. As one of the first companies active in this new marketplace, Enclos has played a leading role in developing this technology through the years into the refined, high-performance curtainwall systems of today. For decades we have built our reputation on professionalism, quality, honesty, integrity, and ingenuity.

Operating under various brand names (Cupples Products, Inc., Harmon Ltd., Enclos Corp.), and mergers, one thing has remained constant: our team is committed to pioneering the course of advanced building enclosures.

1918

THE HALLIDIE BUILDING

WHAT MADE CURTAINWALL POSSIBLE?

William Jenney’s introduction of a steel framing for load-bearing components of structure spawned new possibilities for skyscrapers (late 19th c)

The nation’s first glass curtain wall was built in San Francisco in 1918, the Hallidie Building.

1946

CUPPLES PRODUCTS FORMED AS A DIVISION OF ROBERTSON-CECO

1952

Lever House in Midtown Manhattan is first building in New York to feature a curtainwall

1954

Cupples Products’ first curtainwall: Webb and Knapp Tower, New York Beginning of Cupples Products’ relationship with I.M. Pei

SEMINAL CUPPLES PROJECTS

  1. 1963 | Cadet Chapel – U.S. Air Force Academy, Colorado Springs, Architect: Skidmore, Owings and Merrill U.S. national historic landmark
  2. 1969 | JOHN HANCOCK CENTER, CHICAGO (100 STORIES, 1127 FT), ARCHITECT: SKIDMORE, OWINGS AND MERRILL
  3. 1973 | WILLIS TOWER* (108-STORIES, 1451 FT), ARCHITECT: SKIDMORE, OWINGS AND MERRILL TALLEST UNTIL 1998, * FORMERLY SEARS TOWER
  4. 1973 | WORLD TRADE CENTER, NEW YORK (110-STORIES, 1368 FT), ARCHITECT: MINORU YAMASAKI TALLEST BUILDING IN THE WORLD UNTIL 1973 WHEN SURPASSED BY WILLIS TOWER* 2-MILLION SQ-FT OF ALUMINUM CURTAIN WALL
 

Empire State Building


JOHN HANCOCK CENTER


STANDARD OIL


WORLD TRADE CENTER


SEARS TOWER

 

CUPPLES PRODUCTS LAYS CLAIM TO ENCLOSURES ON 5 OUT OF 6 WORLDS’S TALLEST BUILDINGS



1976

Cupples Products joins forces with its parent, H.H. Robertson Company to carry single source responsibility to the world marketplace, solidifying its position as the largest most completely equipped source dedicated primarily to custom architectural wall systems in the world.

CUPPLES PRODUCTS + H.H. ROBERTSON COMPANY

MANUFACTURING

St. Louis manufacturing facility is now over 400,000 sf, producing some of the most ambitious curtainwall facades for projects across the globe!

  1. 1985 | HSBC BUILDING, HONG KONG (47-STORIES), ARCHITECT: SIR NORMAN FOSTER EXPOSED STRUCTURE AND INNOVATIVE DESIGN MADE THE HSBC BUILDING CONTROVERSIAL, AS WELL AS THE MOST EXPENSIVE BUILDING OF ITS TIME
 

HARMON CONTRACT GLAZING IS FORMED

Spawned from Harmon Glass Company in Minneapolis, Minnesota, originally founded in 1949 for windshields and television screens

1982

Harmon Contract Glazing completes Infomart in Dallas, Texas, a replica of Joseph Paxton’s Crystal Palace (1851)

1994

CUPPLES PRODUCTS, INC. IS FORMED

CH Holdings Inc. purchases Cupples Products’ assets from Robertson-Ceco

1996

Harmon, Ltd. name is introduced for “new construction”

  1. 1997 | GETTY CENTER, LOS ANGELES, ARCHITECT: RICHARD MEIER & PARTNERS ARCHITECTS 12 BUILDING CAMPUS OF GLASS AND TRAVERTINE STONE FACADES ACROSS A 24-ACRE HILLTOP
 

1998

HARMON LTD. UNSEATS CUPPLES PRODUCTS INC. FOR TALLEST

  1. 1998 | PETRONAS TOWERS, KUALA LUMPUR (88-STORIES, 1483 FT), ARCHITECT: CESAR PELLI CUPPLES CLAIM OF REIGN TO ENCLOSING THE TALLEST BUILDING IS TAKEN OVER BY HARMON LTD. WITH THE COMPLETION OF THE PETRONAS TOWERS
 

1999

Harmon Ltd. is purchased by CH Holdings Inc.

2001

UNIFICATION OF INDUSTRY TITANS

Harmon Ltd. is renamed Enclos Corp., and Cupples Products Inc. employees joined Enclos Corp., continuing the legacy

ENCLOS: LEADERS IN FACADE SECURITY

ADVANCED TECHNOLOGY

Enclos was the first in the United States to undertake full-scale bomb-blast testing of curtainwall, even before the events of September 11th, 2001. This pioneering work in blast damage mitigation led to a series of federal courthouse projects for which Enclos was called upon to develop and provide blast-resistant facade systems. Enclos continues to play a leading role in the development and application of risk-mitigating facade technology with respect to security issues.

2007

ENCLOS BRINGS STRUCTURAL GLASS IN-HOUSE

ADVANCED TECHNOLOGY

Seeking to offer the curtainwall products of high-rise towers along with the specialty structural glass facades of jewel-box feature lobbies, Enclos acquires Advanced Structures Inc. (ASI).

2016


NMAAHC


WTC TRANSIT HUB


JEROME GREENE SCIENCE BUILDING


SFMOMA


VIA 57 WEST

 

PIONEERS OF YESTERDAY, TODAY + TOMORROW

Seven decades after Cupples’ origins, and 15 years after merging with Harmon Ltd., Enclos produces a monumental line-up of facades for many of architecture’s most notable projects, including the first ‘courtscraper’ and the largest architectural application of fiber-reinforced polymers (FRP) in the United States.



2022

THE ENCLOS FAMILY OF COMPANIES’ EXPANDED OFFERINGS

Complementary offerings are added to Enclos’ market strategy through acquisition (ETS) and incubation (Coalition Glass).

Enclos forms Enclos Tensile Structures (ETS), a leading specialty contractor of tensile membrane structures with PTFE and ETFE in North America, with the assets and staff acquired from Pfeifer Structures America (formerly FabriTec).

  1. 2020 | SOFI STADIUM, INGLEWOOD, CA   |   learn more
  2. 2009 | ASU SKYSONG INNOVATION CENTER, SCOTTSDALE, AZ   |   learn more
  3. 2019 | ALLIANZ FIELD, SAINT PAUL, MN   |   learn more
Pfeifer Structures, SoFi Stadium, ETFE, PTFE, Enclos, ETS, Enclos Tensile Structures
Pfeifer Structures, Allianz Field, ETFE, PTFE, Enclos, ETS, Enclos Tensile Structures
 

COALITION GLASS

EST. 2022

Coalition Glass is a complementary offering to Enclos, providing glazing and cladding solutions for a wide range of project sizes while maintaining the highest standard of quality, detail, and execution. Our current offerings are design adaptations, procurement, and installation in the Western United States and Hawaii – with plans for expansion into the Eastern U.S. in the coming years.

RECENT ENCLOS PROJECTS


  1. 2018 | AMAZON SPHERES – SEATTLE, ARCHITECT: NBBJ   |   learn more
  2. 2020 | ALLEGIANT STADIUM – LAS VEGAS, ARCHITECT: MANICA ARCHITECTURE   |   learn more
  3. 2019 | 30 HUDSON – NEW YORK, ARCHITECT: KPF   |   learn more
 
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THE ENCLOS FAMILY OF COMPANIES

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