Transcript of "High Tech Building Materials: ETFE"
STUDY OF HIGH TECH BUILDING
The need for new materials
Weightlessness in architecture and design
Material innovations, and the discovery of new materials have served to transform
the ideas of materiality from monolithic to ever more ethereal and ephemeral
From the beginnings of the 19th century to today, glass – composed of
silicates and and an alkalai fused at high temperatures – has ben one of
the most widely used construction materials.
Crystal Palace, Joseph Paxton, 1851
Great icon for lightweight, modular and transparent architecutre
Makes use of mass production processes for iron and glass
Designed such that it could be dismantled after the exhibition, reflecting an attitude toward
mobility that was ahead of it’s time.
Many different kinds of glass have recently entered the construction industry
Photochromic glass : responds to light
Thermochromic glass : responds to heat
Electrochromic technology changes the transparency of glass partitions or cladding from clear to
opaque by passing low voltage electrical charges across microscopically thin coating on surface
IDEO’s recent projects include hi-tech fitting rooms in the New York Prada epicentre, designed
with Rem Koolhaas. Each dressing room is a simple booth with Privalite glass walls that switch
from transparent to opaque for privacy
Replacement for glass needed
- Environmentally friendly
- Energy efficient
- Transparent , light weight
When we think of transparency or translucency, concrete is definitely not a material that
comes to ming.
Concrete connotes solid and durable, opacity and weight.
Bill Price ‘s work on translucent concrete , made of glass and polymerized synthetics.
This has been made possible by embedding an array of tiny glass fibers with concrete
The material, called i.light, was created
specifically for the Italian pavilion at the
2010 World Expo in Shanghai. Italcementi’s
creation was made with a proprietary
mixture of cement and admixtures that
bonds with a thermoplastic polymer resin..
The resin is injected into tiny holes that
span the width of each cement panel,
resulting in approximately 20 percent
transparency. The transparency can be
changed by modifying the amount of resin
in the panels
Free floating structures and lightweight construction materials.
While the aesthetic quality of lightness has become an attribute achieved through
transparency of glass and the airy look of free floating forms; the physical qualities of
lightweight structures tend to concentrate on structural ingenuity and use of lighter
“How much does your building weigh?”, Buckminister Fuller.
He experimented with aluminium at early as the 1930’s.
Hearst Corporation's global headquarters and
the first New York City landmark of the 21st
British architect Norman Foster has conceived
an arresting 46-story glass-and-steel
skyscraper that establishes a number of design
and environmental milestones.
Hearst Tower is a true pioneer in
environmental sustainability, having been
declared the first "green" office building in
New York City.
This is the first such case in any North
American steel-framed skyscraper.
No vertical structural
frames. Gives corner
honeycomb of steel
keeps the interior works
area uncluttered by
pillars and walls, thus
creating superb views of
the city from most
vantages on the work
floors. At night, with its
radically angled panes
of glass, Hearst Tower
looks like a faceted
Diagrid Pattern: More about the Structure
"The triangular frames carry the gravity load
and has inherent strength and resistance to
the lateral loads, seismic and wind
The triangles are so efficient in terms of
bearing both the gravity and lateral loads, the
building use 21 percent less steel (9,500
metric tons) than a conventional building of its
Hearst Tower: Green Building
First green building
completed in New
Hearst Tower is among the
top 10% of energy-efficient
buildings in the nation
Light sensors inside control
the amount of artificial light
on each floor, based on the
amount of natural light
available at any time
Since steel was first mass produced in the 1880s it has always been highly recycled because :
- Steel has a relatively high economic value - the price paid for scrap structural steel in 2012 was
around £200 per tonne
- The versatility of steel means that it can be easily recycled or remanufactured into new
applications as demand dictates
- Steel’s magnetic properties mean that it can be efficiently segregated from mixed waste
90% of the Tower's structural steel contains recycled materials. The triangulated steel frame
uses 21% less steel than a traditionally framed building.
The environmental impact of the first or primary production process is 10 units and the
impact of the secondary or subsequent process, i.e. the recycling process, is 3 units.
The Hearst Tower seems to
have perfect thermal comfort
all year round due to its
complex (and incidental)
An innovative type
of glass wraps
exterior of the
building. The glass
has a special “lowE” coating that
allows for internal
spaces to be
natural light while
keeping out the
Millienium Tower, Glasgow by Richard Horden
The entire structure is mounted on a turntable
and a bearing ring that tapers to fit a single
300mm stainless steel bearing which allows it
to turn towards the wind like a sailboat to
minimize the wind forces.
Aerodynamic design contributes to
A steel tube clad with aluminium located
behind the tower balances it aerodynamically.
Viewing cabin is built out of glass fier
25m tall mast located behind the viewing cabin
is built out of a carbon fiber composite that
improves the natural frequencies of a steel
The "miracle polymer" for public architecture
• ETFE, a fluorine based plastic, was designed to have high corrosion resistance and
strength over a wide temperature range.
• ETFE has a very high melting temperature, excellent chemical, and high energy
radiation resistance properties.
• ETFE film is self-cleaning (due to its non-stick surface)
• It is recyclable.
• In sheet form as commonly employed for architecture, it is able to stretch to three
times its length without loss of elasticity.
• Employing heat welding, tears can be repaired with a patch or multiple sheets
assembled into larger panels.
• ETFE has an approximate tensile strength of 42 N/mm² (6100 psi), with a working
temperature range of 89 K to 423 K (-185 °C to 150 °C or -300 °F to 300 °F).
• ETFE resins are resistant to ultraviolet light. An accelerated weathering test
(comparable to 30 years’ exposure) produced almost no signs of film
• It is prone to punctures by sharp edges and therefore mostly used for roofs.
ETFE has a wide range of applications from wiring insulation, thermoplastic lining, corrosion
protection to wire covers, mold release films.
One of the primary uses of ETFE though, is in the building industry.
Top manufacturer: DuPont
An example of its use is as pneumatic panels to cover the outside of the football stadium Allianz
ETFE provides excellent heat and chemical resistance and mechanical strength.
Beijing National Aquatics Center a.k.a. The Water Cube
90% of the solar energy falling on the ETFE cushions is trapped within the structural zone
and used to heat the pools and interior.
A pump connection and manifold connects
each individual bubble to maintain inflation.
Khan Shatyr Entertainment Center, Astana Kazakhstan
The building encloses an area in excess of 100,000 square metres within an ETFE dome, with
dramatic views over the city and the Steppes beyond.
What is common among all these buildings is the steel structure.
The ETFE pillows are laid out on a steel structure.
J. Baldwin invented a permanent, transparent,
insulated geodesic dome — using a framework of aluminum
tubing, covered with argon-filled laminated vinyl sheet
"pillows" — which he dubbed the "Pillow Dome," said to
have withstood 135-mph winds and thirty inches of
snow. The structure weighed just one-half pound per square
foot of floor space. For a variety of reasons including
durability and toxicity concerns from vinyl chloride vapor
emitted by vinyl sheeting, Baldwin later recommended the
use of ETFE film; ETFE had further advantages including
transparency and ease of keeping the surface clean, but
its ultraviolet transparency reduces its suitability for
occupied structures. Baldwin intentionally did not patent his
invention. The basic approach has since been applied in
large-scale applications such as the Eden Project in Cornwall,
Located in Cornwall, the Eden Project was conceived by Tim Smit and designed by famed
Sir Nicholas Grimshaw is a prominent
English architect particularly noted for
several modernist buildings.
National Space Center, Liecester
Although the structure can be considered
guaranteed for over 60 years.
The covered biomes were inspired by the moon and are constructed from a tubular steel space-fra
with (mostly) hexagonal panels made from a thermoplastic called ETFE.
What better material to use than ETFE for a fantastical project like this- cheaper, lighter and safer t
'An architect would fall over backwards wanting to build something in it,'
said David Kirkland of Nicholas Grimshaw & Partners.
Conception and Erection of
the Eden Project
The Eden Project has three main biomes: the Tropical Biome, the Mediterranean Biome and the
Outdoor Biome (which is uncovered). The Tropical Biome houses plants such as fruiting banana
trees, coffee, rubber and giant bamboo, while the Mediterranean Biome is home to European
plants such as olives and grape vines. The Outdoor Biome is filled with plants that can be grown
outside in the UK climate like tea, lavender, hops, hemp and sunflowers.
The panels vary in size up to 9
metres (29.5 ft) across, with the
largest at the top of the structure.
Although the ETFE is susceptible to
punctures, these can be easily fixed
with ETFE tape.
The ETFE technology was supplied
and installed by the firm Vector
Foiltec, which is also responsible
for on-going maintenance of the
The steel space-frame and
cladding package (with Vector
Foiltec as ETFE subcontractor)
was designed, supplied and
installed by MERO(UK) PLC,
who also jointly developed the
overall scheme geometry with
the architect, Nicholas
Grimshaw & Partners
system that regulates
the temperature and
humidity in each dome
was designed and
installed by HortiMaX
Ltd. (formally named Van
Vliet Automation Ltd.)
who are also responsible
for ongoing maintenance
of the environmental
control and monitoring
systems on both the
Biomes and Glasshouses
at their production site.
The structure is completely self-supporting, with no internal supports, and takes the form of
a geodesic structure. At the lines of intersection between the domes are complex, three-chord,
triangular steel trusses.
The basic form of the construction is a series of
intersecting geodesic domes
This geometry offers a number of advantages: it
facilitates a lightweight yet rigid structure; and it
is easily prefabricated with a plug-in jointing
system that offers a high degree of precision and
can be delivered to the construction site as a
series of small components
The dome construction is divided into two layers: The outer skin is based on a hexagonal
framework, the inner layer on a triangular and hexagonal grid
A challenging point was the design of the support system. Because the 800 m long
foundation varies, each of the 187 support points is geometrically different. The supporting
construction also consists of tubes with diameters of 193 mm which are welded together .
The connecting top chord beams and diagonals are bolted together. The base plates are
fixed to the foundation by anchor bolts M27 and M36 and the horizontal forces are
transferred by shear blocks.
The more than 800 hexagon elements are
covered by air filled cushions
The basic material is between 50
µm and 200 µm thick with a width
of 1.5 m.
The normal cushions are made up of three
layers. The top and bottom layer form the
cushion and carry the loads. An additional
layer between them has the function of
enhancing the temperature insulation and also
dividing up the airspace in case of leakage.
In areas of high local wind suction the outer
surface of the cushions was strengthened by
using two layers of foil.
The cushions are attached on an
aluminium frame to the top chord beams
Each cushion is also attached
to an air supply system
The pressure inside the cushion is about 300
The maximum height of the
inflated cushion is about 10 to 15
% of the maximum span
Material EFTE has been used
for more than 20 years
Cushions in this project size had
never been built.
During the design stage, extensive studies and tests were performed by MERO, the
consultant Ove Arup (London) and the foil subcontractor Foiltec in Bremen (Germany).
Some of the tests were performed on a real 1 to 1 scaled model. The results of this studies
lead to the important parameters for the design of the cushions with spans up to 11 m.
After the design phase, the size of each of the 800 elements was calculated, cut, an
In areas of high show load, like the arches,
some additional cables were needed to
support the cushions.
The gutter construction between the single
domes is made out of insulated aluminium