2. Glass plays an essential role in the facade. A facade is
a special type of wall. It separates inside from outside.
Glass is a uniform material, a solidified liquid. By its
property of transparency it opens up our buildings to
the outside world. In modern architecture there is
tendency to open up our buildings by using very large
facades that are as transparent as possible.
In the external wall, glass can be used as a curtain wall
or structural glazing.
Glass is not essentially transparent. They are available
in several opacities and various textures and finishes.
3. According to ancient-Roman historian Pliny (AD
23-79):
o First discovered in Mesopotamia by
Phoenician Merchants.
o Landed on a beach in Syria
o Propped a cooking pot on some blocks of Nitre
(Potassium Nitrate) placed by their fire.
o Due to the heat of the fire, the blocks melted
and mixed with the sand of the beach creating
melted glass.
4. If heated it softens, melts and becomes a thick
syrupy liquid making it possible to be bent.
Can be blown, drawn, rolled, pressed and cast
into a variety of shapes and textures during in
its molten state.
Commonly used to glaze window, sash and
skylight openings in buildings.
Breaks easily
Waterproof
5. Glass is made from the following raw materials:
Silica (S2O2) 71.0 to 78.0%
Alumina (Al2O3) 0.5 to 1.5%
Iron oxide (Fe203) 0.05 to 0.15%
Calcium oxide (CaO) 5.0 to 10.0%
Magnesium oxide (MgO) 2.0 to 5.0%
Sodium oxide (Na2O) 13.0 to 16.0%
Potassium oxide (K2O) 0.0 to 1.0%
Sulphur trioxide (SO3) 0.0 to 0.5%
7. A type of glass that holds together when
shattered
In the event of breaking, it is held in place by
an interlayer, typically polyvinyl butyral (PVB)
between its two or more layers of glass.
This produces a characteristic “spider web”
cracking pattern when the impact is not
enough to completely pierce the glass.
Usually used for skylight and automobile
windshields.
8.
9. Also known as Tempered Glass.
A glass that has been processed by controlled
thermal or chemical treatments
Has increased strength and enhanced thermal
resistance compared with normal glass and
will usually shatter into small fragments, rather
than sharp shards when broken and therefore
is less likely to cause injury.
Usually used for automobile side and rear
windows, skylights, frameless glass door
10.
11.
12. A type of glass into which a wire mesh is
embedded during production.
Manufactured primarily as a fire retardant,
with wire mesh inlaid in the glass to prevent it
from shattering and breaking out under stress
or when exposed to high temperatures. In case
of breakage, the mesh retains the pieces of
glass.
Can be tinted by aerosol or electricity.
13.
14. Coating of a metal compound applied on one
surface by chemical deposition.
Reflects light and solar heat
May be applied on any type of glass and thickness
upto half an inch
Uses: principally used in curtain wall glazing and
structural glazing, train windows(AC
compartments), doors and windows of commercial
buildings, partitions and internal wall cladding.
Disadvantages: Causes light pollution and is
hazardous to traffic.
15.
16. Flat glass is a sheet of glass made by floating
molten glass on a bed of molten metal,
typically tin. This method gives the sheet
uniform thickness and very flat surfaces.
Modern windows are made from float glass
process. The flat glass process is also known as
the Pilkington process, named after the British
glass manufacturer Pilkington, Alastair
Pilkington pioneered the technique in the
1950s.
17.
18. Sometimes referred to as “figured” or “rolled” glass.
Has a pattern or texture impressed on one or both sides
in the process of rolling.
This glass surface has a patterned decorative design
which provide translucency and some degrees of
obscurity.
Patterns are classified as decorative or glazing
Uses: decorative glazing of windows, bathroom
partitions, door.
Is difficult to clean as dust settles between the crevices
Thickness: 4mm, 6mm,
Sizes: 2140 x 1280 mm, 2140 x 1320 mm respectively.
19.
20. Also known as glass block, is an architectural
element made from glass. Glass bricks provide
visual obscuration while admitting light.
Glass bricks are produced for both wall and floor
applications.
Use in floors are manufactured as a single solid
piece, or as a hollow glass block with thicker side
walls than the standard wall blocks.
Hollow glass wall blocks are manufactured as two
separate halves and, whilst the glass is still molten,
the two pieces are pressed together and annealed.
21. To bed the blocks together in a Portland
cement-based mortar with reinforcing rods of
steel placed within the mortar.
Other methods of construction include several
proprietary systems whereby the mortar is
replaced by timber or PVC extrusions.
22. Bullet and vandal resistance
-Bullet and vandal resistant blocks are generally solid glass or
have very thick side walls similar to pavement blocks.
Fire resistance
-Resistance is improved by utilizing specially produced hollow
blocks with thicker sidewalls, or the inclusion of a special layer of
fire resisting material between the two halves of the block during
manufacture.
Gas insulated
-Inclusion of argon gas within the hollow center of glass wall
blocks offers significantly improved thermal insulation properties.
Colored
-Some hollow glass wall blocks are available in colored variants.
These colored variants fall into two categories; those that are
manufactured with colored glass which are UV stable and can be
used in the same locations as standard clear glass blocks.
23.
24. Body tinted glass products are produced by small additions
of metal oxides to the float or rolled glass composition.
These small additions color the glass
bronze, - selenium oxide
green, - iron oxide
grey – cobalt oxide
blue - additional cobalt oxide
but do not affect the basic properties of the glass except for
changes in the solar energy transmittance. The color is
homogeneous throughout the thickness.
weak colors by transmitted light. They do not produce high
or significantly colored reflectances. Usually their principal
external visual characteristic is their lower light
transmittance.
25.
26. Insulated glazing (IG), more commonly known
as double glazing (or double-pane, and increasingly
triple glazing/pane) is double or triple glass window
panes separated by a vacuum or other gas filled space
to reduce heat transfer across a part of the building
envelope.
Insulated glass units are manufactured with glass in
range of thickness from 3 mm to 10 mm (1/8" to 3/8")
or more in special applications. Laminated or tempered
glass may also be used as part of the construction. Most
units are manufactured with the same thickness of
glass used on both panes but special applications such
as acoustic attenuation or security may require wide
ranges of thicknesses to be incorporated in the same
unit.
27.
28. These are glass products that have been
strengthened by means of an ion-exchange
process.
typically six to eight times the strength of float
glass.
Glass is submersed in a bath containing a
potassium salt at 300°C. This causes sodium
ions in the glass surface to be replaced by
potassium ions from the bath solution.
29.
30.
31. Thin film coatings are applied to the raw soda-lime glass, to improve thermal efficiency
(insulation properties)
Coatings are microscopically thin, virtually invisible, metal or metallic oxide layers deposited on a
window or skylight glazing surface primarily to reduce the U-factor by suppressing radiative heat
flow.
Two primary methods in use: pyrolytic CVD and magnetron sputtering..
The first involves deposition of fluorinated tin oxide at high temperature. Pyrolytic coatings are
usually applied at the float glass plant when the glass is manufactured.
The second involves depositing thin silver layers with antireflection layers. Magnetron
sputtering uses large vacuum chambers with multiple deposition chambers depositing 5 to 10 or
more layers in succession.
32.
33. Is a specific type of glass with a surface that keeps
itself free of dirt and grime.
The glass cleans itself in two stages.
The ‘photo catalytic’ stage of the process breaks
down the organic dirt on the glass using ultraviolet
in sunlight (even on the overcast days) and makes
the glass hydrophilic (normally the glass is
hydrophilic). During the following ‘hydrophilic’
stage rain washes away the dirt-leaving almost no
streaks, because hydrophilic glass spreads the
water evenly over its surface.
Editor's Notes
Glassmaking was discovered 4,000 years ago, or more, in Mesopotamia. The Roman historian Pliny attributed the origin of glassmaking to Phoenician sailors. He recounted how they landed on a beach near Ptolemais (in modern-day Israel), propped a cooking pot on some blocks of natron (a naturally-occurring alkali substance) they were carrying as cargo, and made a fire over which to cook a meal. To their surprise, the beach sand beneath the fire melted and ran in a liquid stream that later cooled and hardened into glass. Though this is an interesting explanation, this scenario is not possible since a cooking fire cannot reach the melting temperature of glass, and the story most likely involved Ptolemais because its beach sand was historically known to be heavily used for glassmaking.
The ancient-Roman historian Pliny (AD 23-79), describes how Phoenician merchants transporting stone, actually discovered glass accidentally, in the region of Syria around 5000 BC. After landing on a shore, the merchants placed cooking pots on blocks of nitrate placed by their fire. The intense heat of the fire caused the blocks eventually to melt and mix with the sand of the beach and formed an opaque liquid. Glass.
http://vision2form.nl/glass_history.html
http://www.historyofglass.com/
http://www.historyofglass.com/glass-history/glass-making/