Glass and Glazing

Question 1

materials in clear glass

Answer 1

silica sand +

small amounts alkaline salts (ex. lime, potash, soda)

Question 2

annealed glass aka

Answer 2

float glass

Question 3

annealed glass

manuf. process:

Answer 3

pouring molten glass,
on bed of molten tin.
slowly cool.

Question 4

heat-strengthened glass

manuf. process:

Answer 4

glass heated to 1100ºF,
slowly cooled.
2x strength annealed glass.

Question 5

heat-strengthened glass

use:

Answer 5

solar-induced thermal stresses,

cyclic wind loading.

Question 6

tempered

manuf. process:

Answer 6

subjecting annealed glass to a special heat treatment,
heated to 1150ºF and quickly cooled.
process sets up compressive stresses @ outer surface,
and tensile stresses @ inner surface.
4x stronger.

Question 7

tempered

typ thickness:

Answer 7

⅛” to ⅞”.

Question 8

tempered glass breaking scheme

Answer 8

breaks into tiny pieces, instead of dangerous shards.

Question 9

laminated glass

manuf. process:

Answer 9

two or more pieces of glass,
bonded by polyvinyl butyral resin.
when broken, interlayer tends to hold together.

Question 10

laminated glass

use:

Answer 10

bullet resistance,

sound control

Question 11

laminated glass thickness:

Answer 11

13/64” to 3”

Question 12

tinted glass or heat absorbing glass

not used at

Answer 12

differential expansion

not used where combination direct sun/shade,
will crack under thermal load.
solution: tinted glass often heat strengthened/tempered.

Question 13

ratio solar heat gain at specific fenestration,
to shg at ⅛” clear glazing.
doesn’t include frame/spacer effects.

Answer 13

shading coefficient:

Question 14

ratio solar heat gain through glazing/wdw,

to total solar radiation incident on glazing/wdw.

Answer 14

solar heat gain coefficient:

Question 15

gives light-green color,
to ordinary float glass.
pros: exceptional clarity, light/color transmission.

Answer 15

low-iron glass:

Question 16

clear or tinted glass, coated w thin layer,
of metal or metallic oxide.
placed on inside face of exterior lite.
color: silver, copper, golden, earthtone shades

Answer 16

reflective glass:

Question 17

fabricated of two or three sheets,
hermetically sealed air space of ¼-½”.
can be made w heat-strengthened, tempered,
reflective, tinted, laminated.

Answer 17

insulating glass:

Question 18

smooth or patterned surface,
used primarily fire-rated, in non-hazardous locations.
50% stronger than annealed glass.
cannot be tempered.

Answer 18

wire glass:

mesh of wire embedded in middle of sheet.

Question 19

conceals floor and ceiling in curtain wall construction

Answer 19

spandrel glass:

Question 20

used as the opaque glass,
permanently fuse ceramic frit color,
to back of heat-strengthened or tempered glass.
typ single sheet w insulation behind.

Answer 20

spandrel glass:

Question 21

selectively reflects certain wavelengths.
very thin coating (few atoms) of metal or metal oxide,
on surface of glass or thin film.
transmits visible light and short wave solar radiation,
but reflecting long-wave heat radiation.

Answer 21

low-emissivity glass:

Question 22

low-emissivity film most effective when located:

Answer 22

middle of glass

u-value 0.23

Question 23

used as a general category term.
either dark tint or milky white opaque,
changes to transparent when electric current is applied.

Answer 23

electrochromic glazing:

Question 24

electrochromic glazing:

type provides light control

Answer 24

electrochromic glazing

Question 25

electrochromic glazing:

type provides light and privacy control

Answer 25

SPD (suspended particle device)

Question 26

electrochromic glazing:

type provides privacy control

Answer 26

polymer-dispersed liquid crystal film

Question 27

polymer film between two layers glass,
in translucent, offers full visual privacy.
still lets significant light through,
so not good for light control.

Answer 27

polymer-dispersed liquid crystal film

Question 28

light-absorbing microscopic particles,
dispersed in liquid suspension film,
between 2 layers transparent conductive material.
can be totally opaque (privacy).
variation w rheostat switch.

Answer 28

SPD (suspended particle device)

Question 29

inorganic ceramic thin-film coating on glass,
range from transparent to heavily-darkened.
never totally opaque, so not good for privacy.
variation w rheostat switch.

Answer 29

electrochromic glazing