“…do you want first to build scaffolding out of steel, visible, preferably naked and

powerful…”

from wall to skin

The Evolution of Transparency: IRON

Palm House

Richard Turner & Decimus Burton

London, 1844-48

Passage Jouffroy

Paris, 1847

The Evolution of Transparency:

Releasing the External Wall from its Loadbearing function

Carson Pirie Scott

Louis Sullivan

Chicago, 1899-1904

Fagus Works

Walter Gropius

Altfred an der Leine, 1911

Paxton:

Crystal Palace foreshadows industrial curtain walls

Gropius:

Bauhaus early steel and glass curtain wall

SOM

Lever House: early 1950s curtain wall (Ferriss rendering)

Steiff Works

Giengen

1903-11

Façade Elevation & Section

The Evolution of Transparency:

Daylighting and Thermal Control

The Evolution of Transparency:

Daylighting and Thermal Control

Open Air School

Jan Duiker

Amsterdam, 1927-28

Van Nelle Tobacco Factory

Johannes Brinkman

Amsterdam, 1926-30

The Evolution of Transparency:

The Glass House

Glass House

Philip Johnson

New Canaan, CT

1948

Eames House

Charles & Ray Eames

Pacific Palisades, CA

1949

The Evolution of Transparency:

Daylight & Darkness

Notre-Dame-du-Haut

Le Corbusier

Ronchamp

1951

Church of Light

Tadao Ando

Ibaraki, Japan

1987-9

Crystal Cathedral

Philip Johnson & John Burgee

Garden Grove, CA

1980

Bruno Taut:

Glass pavilion (1914) as harbinger of enlightened culture

Foster:

Reichstag dome as modern version of same theme

The Evolution of Transparency:

Translucency

Goetz Art Gallery

Herzog & de Meuron

Munich, 1994

Lloyd’s Building: Façade Detail

Richard Rogers

London, 1982-6

Bregenz Art Gallery: Façade

Peter Zumthor

1997

Les 3 Cartier

The Evolution of Transparency:

Transparency

The Evolution of Transparency:

Transparency

Two Views of the Celia Franca Centre Demonstrate the Dynamic of the Curtain Wall

Harrison and Abramovitz: Socony Mobil Building with steel

panels.

Richard Meier:

Getty Center's metal panel system.

The Evolution of the Curtain Wall:

Materials

I.M. Pei:

Hancock Building as reflective, crystalline surface

Cesar Pelli

Pacific Design Center sculptural reflective surface

Mies van der Rohe

Seagrams Building metal and glass "woven" grid

Stubbins

Citicorp Center with metal and glass curtain wall.

Seagram Building

•  Ithaca, NY

•  Opaque spandrels create a ribbon effect on the façade of the building.

•  Colored or tinted glass used to change the appearance of the building as well as the quality of light filtering into the building.

Foster

Willis Faber Dumas

building literally hangs curtain of transparent/reflective glass

Roche & Dinkeloo

UN Hotel

uses curtain wall to reinforce abstract gridded geometry

Nouvel:

Foundation Cartier explores issues of transparency

Grimshaw:

Waterloo Terminal uses "structural" glass without mullions

Glass is a supercooled liquid. It has no fixed melting point and an open non-crystalline microstructure

•  Glass begins with the following mix or “frit”

–  ~69% silicon dioxide (very fine sand) •  melts at 1700°C but is too gooey to work

–  ~17% soda ash (alkaline) •  reduces melting temperature (900°C) making a more

workable mixture –  ~11% lime (and magnesia)

•  resists attack by water that would destroy the glass –  ~ 3% alumina, iron oxide and manganese oxide

•  color, stability

The Manufacture of Glass:

Composition

Crown glass

Cylinder Glass

The Evolution of Transparency: The Crystal Palace

Joseph Paxton

London, 1851

Façade Details

The Evolution of Transparency: The Crystal Palace

Joseph Paxton

London, 1851

Vent Detail Glazed with 900,000 SF of cylinder glass on a cast iron structure (in 17 weeks)

•  plate glass: cast glass, rolled out in a pan, polished

•  drawn glass: pulled vertically through rollers

•  float glass: pulled horizontally over

•  annealed glass: cooled slowly under controlled conditions

•  tempered glass: re-heated to 1200°F and cooled quickly so the glass on the surfaces is placed in compression and interior in tension (glass contracts as it cools) (4X’s stronger than annealed)

•  laminated glass: sandwich of polyvinyl butyral (PVB) between two sheets of glass and bonded under heat and pressure (can be colored or patterned)

The Manufacture of Glass:

Types and terms

Glass (Methods of Manufacturing)

Making Float Glass

Pilkington Brothers, Ltd. started production of float glass in 1959

•  based on the fact that the specifically lighter of two non-mixable liquids (molten glass) will float on the heavier liquid (tin)

•  produces a continuous ribbon between 3 and 4 meters wide

•  thickness is 6-7 mm naturally (less by speeding, more by slowing—up to 35 mm)

1500°C 1100°C 1050°C 600°C 500°C 200°C

<------------------------------------------200m--------------------------------!

manufactured in standard thicknesses: 3/32” = single-strength 1/8” = double-strength up to 1” thick

glass is usually warehoused in 6 meter lengths (less than 4 meters wide)

Structural Glass:

Laminated Glass

laminated safety glass: the intermediate layer retains the pieces of broken glass in case of a break

Tempered Glass

1.  How to support the weight of the glass

2.  How to support the glass against wind pressure and suction.

3.  How to isolate glass from structural deflections of frame and the frame from the mullions

4.  How to allow independent expansion and contraction of glass and frame

5.  How to avoid glass contacting any other materials that could scratch or stress it.

The Manufacture of Glass:

Design considerations for large-light glazing systems

The Evolution of Curtain Walls

Examples

structural support

inside

outside

General Motors Jespersen Office Block Lever Building

plan

section

Lever Building, New York

SOM 1952

Load-bearing rolled steel sections concealed behind folded stainless steel sheet.

Single pane glass held in place by putty

spandrel panel

The Evolution of Curtain Walls

Examples

plan

section

Jespersen Office Block, Copenhagen,

Arne Jacobsen, 1955

wood supports

green glass spandrel panels

The Evolution of Curtain Walls

Example: Jespersen Office Block

plan

section

General Motors Technical Center, Warren, Michigan

Eero Saarinen, 1949-56

Totally prefabricated curtain wall

Synthetic, permanently elastic rubber profiles (neoprene)

The Evolution of Curtain Walls

Example: General Motors Technical Center

Types of Cladding Systems

• Storefront –  inserting glass frame into the building fabric

• Standard Curtainwall –  engineered system –  (shear block mullions, pressure bar, beauty spot)

• Custom Curtainwall

• Structural Glazing –  glass walls

Curtain Wall Systems

Stick System In the system, the wall is installed piece by piece.

The mullion members are installed first, followed by the transoms, the panels, and then the glazing or window units. The stick system was used extensively in the early years of metal curtain wall development, and is still in wide use.

Unit System The wall is composed entirely of large framed units pre-

assembled at the factory. The vertical edges of the units join to form mullion members, top and bottom members join to form horizontal rails.

Unit and Mullion System The wall system is a compromise between the

stick and unit system. First, the mullion members are installed separately, then pre-assembled framed units are placed between them.

Column Cover and Spandrel System In the system, the column cover

is installed first which may be one or two stories in height, then the long spandrel panels which span between the column cover are placed between them. Finally, the glazing infills are fixed with the frame.

Stick Systems •  tubular metal mullions

and rails assembled piece by piece on site.

Lever Building, New York SOM 1952

The Evolution of Curtain Walls

Example: Lever Building

•  The framing panels of a curtain wall may be supported in one of two ways: –  by the columns alone –  by the columns as well

as by spandrel beams or the edges of floor slabs

whether the primary building structure is:

–  structure steel frame

–  reinforced concrete

Glazing Construction:

Curtain Wall

The Assembly of Curtain Walls

The Assembly of Curtain Walls

The Assembly of Curtain Walls

The Assembly of Curtain Walls

The Assembly of Curtain Walls

The Assembly of Curtain Walls

The Assembly of Curtain Walls

The Assembly of Curtain Walls

The Assembly of Curtain Walls

inside

outside

The Assembly of Curtain Walls

The Assembly of Curtain Walls

The Assembly of Curtain Walls

Unit Systems preassembled, framed wall units

Unit and Mullion Systems •  one or two-story high

mullion are installed before preassembled wall units are lowered into place behind the mullion.

Glazing Construction: Assembly

•  On site glass elements are

either individually fixed to a loadbearing construction or they are joined together to form a coherent, self-supporting structure.

•  Owing to the transparency of the material, the discontinuity at joints is particularly noticeable so alignment is critical.

•  Glass elements must be connected in such a way that the filtering or sealing functions are properly fulfilled.

Unitized systems

Terminal One of the Toronto International Airport

•  a unitized system with silicone on four sides •  design flexibility with multiple interconnecting

panel types

The Celia Franca Centre National Ballet School in Toronto KPMB Architects and Goldsmith Borgal

Column-cover-and-spandrel systems •  these systems consist of vision-glass assemblies and

spandrel units supported by spandrel beams between exterior columns clad with cover sections.