Glass:Glass: The Right Choice

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• AAMA is a registered provider with the American Institute of Architects’ continuing education program. Credits earned upon completion of this program will be reported to CES records for AIA members. Certificates of completion for non-AIA members

il bl tare available upon request.

• This program is registered with the AIA/CES for continuing professional education. As such, it does not include content that may be deemed or construed to be an approval or endorsement by the AIA of any material of construction or any

th d f h dli i di t ib ti d li imethod or manner of handling, using, distributing, or dealing in any material or product. Questions related to specific materials, methods, and services will be addressed at the conclusion of this presentation

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this presentation.

This presentation is protected by U.S. andThis presentation is protected by U.S. and international copyright laws. Reproduction,

distribution, display, or other use of the presentation without written permission from

the speaker is prohibited.

© AAMA Glass Material Council 2008

L i Obj tiLearning ObjectivesThis course is designed to improve your

• Uses of glass

understanding of:

• Types of glass• Fabricated glass solutions

M i d l ti l f• Measuring and evaluating glass performance

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SECTION 1

Glass Functionality

SECTION 1

Glass Functionality and Performance

Glass: How It Functions in a BuildingConstruction utilizing glass offers many unique advantages:

• Protection from the elements • Natural light• View of the outdoors• Strength to weight ratio superior to concrete, which allows the

use of smaller, less costly foundations

Using readily available and efficient glassmaking technologies, glass can be specified to meet the four main functions of glass in a wall: 1 C l ti ll th ti1. Complementing overall aesthetics2. Meeting life and safety requirements3. Maximizing energy efficiency4 P idi f t bl d ti it

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4. Providing comfortable productivity

Gl F ti d S l EGlass Function and Solar EnergyThree elements that can be reflected, absorbed, or transmitted by commercial windows and doors:

1) Ultraviolet (UV) light• Not visible• Represents only about 3% of the solar spectrum

2) Visible light2) Visible light• Detected by human eye (perceived as “daylight”)• Represents approximately 38% of the solar spectrum

3) Infrared light• Occurs at wavelengths just below red light—hence the name

“infra” or “below” red

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• Represents approximately 59% of the solar spectrum

S l E A K C id tiSolar Energy: A Key Consideration for Architects

There is a broad spectrum of energy aroundenergy around us everyday—but solar energy is unique for its

780700

Wavelength (nm)

ability to impact the energy performance and comfort of

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500

Visible

Light

and comfort of commercial structures.400

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H I S l E T f d?How Is Solar Energy Transferred?Three ways to heat the atmosphere or any physical y p y p ysubstance:

1)Conduction: Heat transfer through solid matter1)Conduction: Heat transfer through solid matter through direct contact with a hot or cold surface

2)Convection: Heat transfer through a moving fluid ) g g(liquid or gas) across or around solid matter

3)Radiation: Heat transfer in the form of electromagnetic waves from one matter to anotherelectromagnetic waves from one matter to another regardless of matter form

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H t G i d L i B ildiHeat Gain and Loss in BuildingsThree components of solar heat gain in a commercial structure:

• Transmitted solar energyTransmitted solar energy• Reflected solar energy• The inward-flowing part of the solar energy absorbed by glass

Components of total heat gain (or heat loss):• Differences in temperature between interior and exterior spaces can

also cause heat gain (or heat loss, in cold climates).

convectionconvection

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T t l Gl P fTotal Glass Performance: Beyond Solar Energy

While solar heat gain is an important measure of glass performance for energy efficiency and comfort, it is just the first in a long list of glass performance characteristics that g g parchitects must understand and consider:

• Solar Heat Gain Coefficient• Solar Heat Gain Coefficient• U-Factor• Light Transmittance• Damage-Weighted Index• Light-to-Solar Gain

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• The Solar Heat Gain Coefficient (SHGC) is the fraction

Glass Performance: Solar Heat Gain

• The Solar Heat Gain Coefficient (SHGC) is the fraction of solar radiation that is transmitted through architectural glass—expressed as a number between 0 and 10 and 1.

• The lower a window’s SHGC, the less solar energy it , gytransmits—and the greater its shading ability.

• SHGC can be expressed in terms of glass alone or• SHGC can be expressed in terms of glass alone—or can reflect the performance of an entire window assembly including the frame.

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Gl P f U F t• U-Factor is a measure of how well a

Glass Performance: U-Factor

material transmits heat.

• The lower the U-Factor, the greater a window’s resistance to heat flow—andwindow s resistance to heat flow and the better its overall insulating value.

• U-Factor using imperial measurements are expressed in units of BTU/hourare expressed in units of BTU/hour-square foot-°F.

• U-Factor can be calculated for glass alone or—more commonly—for an entire window unit, including the frame and spacer materials that help to impro e ins lation

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improve insulation.

Gl P f Li ht T itt

• Visible Light Transmittance (VLT) – The fraction of solar

Glass Performance: Light Transmittance

Visible Light Transmittance (VLT) The fraction of solar radiation in the visible light wavelengths that passes through the glass.

R dil il bl l d t f t d ’ i l• Readily available glass products for today’s commercial construction projects range from 0% VLT up to and including glass products in the mid-90% VLT.

• An emerging measure—the Damage-Weighted Index—helps architects to assess the potential for fading far more accurately than looking at VLT measures alone.y g

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Glass Performance:Glass Performance: Damage-Weighted Index

The Damage-Weighted Index, which combines both visible and ultra violet radiation, helps architects assess the potential for fading far more accurately than looking at ultra violet measures alone.

Two ways of calculating the DWI for architectural glass andTwo ways of calculating the DWI for architectural glass and window units:

1) Tdw-K: Created by Europe’s Jurgen Krochmann, this measure covers the UV and visible parts of the spectrum from 300 to co e s t e U a d s b e pa ts o t e spect u o 300 to500 nm.

2) Tdw-ISO: A more comprehensive measure—recommended by Commission Internationale de L’Eclairage—this measure

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gcovers the solar spectrum from 300 to 700 nm.

Gl P f Li ht t S l G iGlass Performance: Light-to-Solar Gain

• Light-to-Solar Gain (LSG), emerging as an important glass performance measure, is a gauge of the efficiency of a glass product in transmitting daylight—while blocking solar heat gaingain.

• LSG is the ratio between VLT and SHGC (LSG = VLT/SHGC).

• U.S. Department of Energy defines spectrally selective glass as glass with a Light to Solar Gain ratio of 1.25 or higher. The higher the LSG, the more energy efficient the glass product g , gy g pis.

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SECTION 2SECTION 2

Different Glass Types—for Varying Performance NeedsVarying Performance Needs

O i f Diff t Gl TToday, architects can choose from a wide range of glass

Overview of Different Glass Types

products that meet different criteria for functionality and performance:

• Float• Rolled• CoatedCoated

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Fl t Gl A I d t St d dFloat Glass: An Industry Standard

• The architectural glass found in most buildings today is commonly referred to as “float glass,” which consists primarily of silica sand, soda, and lime.

• In the float manufacturing process these materialsIn the float manufacturing process, these materials are heated to their molten state—then drawn over a liquid bath of tin, before the mixture is cooled under controlled conditions Because tin has a highercontrolled conditions. Because tin has a higher specific gravity than molten glass, the glass “floats” on the tin—forming a perfectly flat layer.

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The Float Glass Process:The Float Glass Process: Mixing the Batch

The “batch” is digitally weighed and mixed with cullet, as well as small amounts of other materials—then transferred by conveyor into the batch

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house. The batch is continuously fed into the furnace, where it is melted.

The Float Glass Process: MeltingThe Float Glass Process: Melting

The batch materials are continuously fed into the furnace, where they are heated to their melting point. The molten glass flows to the end of the

furnace where it moves through a canal onto a pool of liquid tin

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furnace, where it moves through a canal onto a pool of liquid tin.

The Float Glass Process:The Float Glass Process: Glass Ribbon Formation

As the glass moves over the liquid tin, metal knurls contact the glass ribbon at its edges—helping to control both its width and speed. The

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molten glass “floats” and forms a perfectly flat layer.

The Float Glass Process: Pyrolytic CoatingThe Float Glass Process: Pyrolytic Coating

As the glass ribbon is pulled over the liquid tin, reflective or low-E coatings can be applied to the “atmosphere” surface of the glass. These coatings

k l ti “h d” t

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are known as pyrolytic or “hard” coats.

The Float Glass Process: AnnealingThe Float Glass Process: Annealing

Lifted out by rollers, the glass ribbon finally leaves the tin bath. Now it is cooled slowly or “annealed” in order to remove any residual stresses and

make it stronger After annealing the glass can be cut into pieces

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make it stronger. After annealing, the glass can be cut into pieces.

The Float Glass Process: CuttingThe Float Glass Process: Cutting

Cooled glass passes through inspection booths to ensure that it has the uncompromising quality needed for its end use. Defects are marked, and

the rough edges are trimmed. The remainder is cut for packaging. The

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g g p g gglass is then inventoried and ready to be shipped.

Fl t Gl P d tThree Categories of Glass Substrates:

Float Glass Products

1) High Solar Transmittance (approximately 70-90%)• Absorb little of the heat energy from the sun providing little protection

from solar heat gain and potentially damaging UV and visible light• Offer excellent clarity and color neutrality

2) Medium Solar Transmittance (approximately 40-50%)• Provide more protection against solar heat gain and visible light p g g g

transmittance• Features color

3) Low Solar Transmittance (approximately 33% or less)• Provide excellent protection against solar heat gain, as well as high

levels of damaging light transmission• Heavily colored

26Note: Solar heat gain can actually be beneficial in cold, northern climates

El Fl t Gl S b t t1) Lower-Performing Glass Substrates

Clear Low-Iron

Eleven Float Glass Substrates

2) Medium-Performing Glass SubstratesGreen BronzeG Bl GGray Blue-Green

Blue

3) Higher-Performing Glass Substrates3) Higher Performing Glass SubstratesAzure Dark BlueDark Green Dark Gray

Clear Green Gray Bronze Blue- Blue Azure Dark DarkLow-Iron Dark

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Clear Green Gray BronzeGreen

Blue AzureGreen Blue

Low IronGray

R ll d Gl A P tt d O tiRolled Glass: A Patterned Option

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R ll d Gl A li tiRolled Glass ApplicationsPatterned Glass

I t i d t i d ti l t i ll i h i• Interior and exterior decorative elements, especially in heavier glass thicknesses

Rolled Glass • Help channel or direct visible light energy to be used in lighting

panels, including solar or photovoltaic cells

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C t d GlCoated Glass: Customized Performance

• “Hard” or Pyrolytic Coatings applied during the float process that become part of the finished glass itself

• “Soft” or Sputter Coatings appliedSoft or Sputter Coatings applied through a magnetic sputter vapor deposition process separate from the float glass process

• Reflective and Low-Emissivity Coatings offer excellent solar control,

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g ,minimizing heat gain

Surface Orientation:Surface Orientation: The Science of the Surface

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Low E Coatings:Low-E Coatings: Outstanding Thermal Performance

“E i i it ” i f“Emissivity” is a measure of a material’s ability to re-radiate absorbed infrared radiation.

Low-emissivity or “low-E” glass coatings

• Metallic layers applied to float glass to reflect radiant energy back toward its source

• Heat stays outside during the summer, and inside during the winter

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Location of Low E Coatings:Location of Low-E Coatings:Critical to Performance

To maximize the performance of low-E coatings, there are some g ,general guidelines:

• The U-Factor is the same, whether low-E coatings are placed on surface 2 or 3

• The SHGC is generally lower with low-E coatings on surface 2

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P l ti C ti H d B fitPyrolytic Coatings: Hard BenefitsGlass products that feature a pyrolytic coating have a

b f d t• Easy to handle, transport, stack,

and store

number of advantages:

• Can be heat-treated and laminated to meet specialized applicationspp

• Durable enough to be used monolithically – consult with product manufacturer for detailsp

• Can be exposed to weather—positioned on the #1 surface—but this is not recommended as the Damage to Low-E coating that was placed on the

#1 surface and cleaned using an organic cleanser.

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coating may be easily damaged.#1 surface and cleaned using an organic cleanser.

Sputter Coatings:

“Sputter” or “soft” glass coatings are applied through

Sputter Coatings: Soft on Energy

“Sputter” or “soft” glass coatings are applied through the bombardment of metal atoms onto the surface of float glass.

Though less durable than pyrolytic coatings, they offer many benefits:many benefits:

• Versatile, can be applied to any glass substrate• Cover the full range of performance and aesthetic

requirements (literally hundreds of sputter coating possibilities)

• Feature new post-temperable technologies that allow them

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to be heat-treated

Reflective Coatings:Reflective Coatings: Superior Solar Control

R fl ti Gl C ti t lli lReflective Glass Coatings are metallic layers applied to float glass in order to reflect short-wavelength solar energy back into the atmosphere. g gy p

Though reflective coatings can make glass very hot, its benefits include:its benefits include:

• Significantly reduce solar heat gain, making interior spaces cooler and more comfortable

• Lower the capital costs needed for air-conditioning systems

• Reduce ongoing air conditioning expenditures

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• Provide a distinctive appearance for architectural facades

Vi i C t d Gl P d tViewing Coated Glass Products

Reflective Glass• Most of the light reaching the observer

is reflected from the coatingg

• Little read-through

• View in a vertical position, against a dark backgrounddark background

Low-E GlassLow E Glass• A lot of transmitted light

• Significant read-through

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• Assess in a vertical position, against a medium- or dark-colored background

SECTION 3SECTION 3

Fabricated Glass Solutions—Taking Performance

One Step Further

O i f F b i t d S l ti

Fabricated glass products that are widely available

Overview of Fabricated Solutions

Fabricated glass products that are widely available include:

H t T t d• Heat-Treated• Laminated• InsulatingInsulating• Fire-Rated• Spandrel• Silkscreen

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Heat Treated Glass:Heat-Treated Glass: Stress-Resistant Solutions

• All float glass is annealed—or cooled slowly—after manufacturing to remove residual stresses and make the glass strongerthe glass stronger

• Heating the glass can strengthen it for use in some specific applications

• There are two common heat treating methods used to• There are two common heat-treating methods used to strengthen glass:1)Heat Strengthening

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2)Tempering

What Causes Thermal Stress?What Causes Thermal Stress?Contributing Factor Importance Rating (1-10)

10 being the most importantEdge quality 10Energy absorption of glass (tinted, reflective) 8Shading from overhangs 8g gShading from vertical members 7Altitude of building (solar intensity and temp. change) 7Geographic location of building 6Geographic location of building 6Heat sinks 4Inclusion of low-E coating 4Use of labels on glass 4Adjacent reflective surfaces 4Color of window frame 3

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Interior shades 3Glass size 3

Heat-Strengthened Glass

• Annealed glass is reheated to a high temperature, then cooled quickly in a process called “quenching”—making it twice as strong.

• Heat-strengthened glass is used in spandrels, windows in g g p ,high wind load areas and applications where the glass has a risk of thermal stress.

• Heat strengthening does not result in a “safety” glassHeat strengthening does not result in a safety glass product; it breaks in a pattern similar to annealed glass.

T d GlTempered Glass

• Similar to heat strengthening but cooled with a much more g gintense air flow during the “quench” phase. Four times stronger than annealed glass.

• Breaks into small pebble-like pieces resulting in significantlyBreaks into small, pebble like pieces resulting in significantly less safety hazard.

• Excellent for commercial storefronts, entryways, display cases, railings sk lights and o erhead lighting fi t resrailings, skylights, and overhead lighting fixtures.

H t S k d GlHeat-Soaked Glass

• Tempered glass is frequently specified to meet higher wind loads and ensure safety in large glass installations.

• Heat soaked glass is a solution that helps to reduce the risk of spontaneous breakage.

• While many international building codes demand heat-soaked glass this trend is only beginning to i t N th A i hit timpact North American architecture.

Laminated GlassLaminated Glass• Laminated glass consists of two or more lites of glass bonded

together by a plastic interlayer. g y p y

• When broken, the glass fragments remain bonded to the plastic interlayer to retain the lite in the opening and reduce hazard potential.

• Customized applications for laminated glass products include f t it h i i t d d t lsafety, security, hurricane resistance, and sound control.

Photo courtesy of GANA

Laminated Glass Applications: Safety

U d f t l i• Used as safety glazing in commercial and residential construction

• Retains glass shards within framing system

• Building codes often require laminated safety glass for storefronts, entrance doors, and overhead glazingsg g

Laminated Glass Applications: Security

• Oklahoma City bombing in 1995 and terrorist• Oklahoma City bombing in 1995 and terrorist attacks of September 11, 2001 have increased focus on laminated glass for security and protection.

• Laminated glass products are integral components to design for blast and ballistic protection.

• Can also be designed for protection against forced entry while allowing for emergency access and egress.egress.

• Specialized laminated products are available that also protect against electronic eavesdropping and g gelectromagnetic interference.

Laminated Glass Applications:Laminated Glass Applications: Hurricane Resistance

• Laminated glass meets new• Laminated glass meets new hurricane resistance building codes.

• Glazing and framing impacted with either large missile (9 lb. 2x4 @ 34 mph) or small @ 3 p ) o s amissiles (2 gram steel shot @ 88 mph) without penetration

S t th l d• System then pressure cycled 9000 times and glazing must remain in opening 373 Photography

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Laminated Glass Applications:Laminated Glass Applications: Sound Control

• Multi-layer construction dampens the transmission of certain sound frequencies

• Significantly increases Sound Transmission Loss (STL) to improve Sound Transmission Class (STC) and ( )Outdoor-Indoor Transmission Class (OITC)

• Dramatically improves sound controlDramatically improves sound control characteristics near airports, highways, railroads, manufacturing facilities, etc.

Also sed for interior so nd control in

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• Also used for interior sound control in audio studios and other production environments.

Fi R t d Gl O tiFire-Rated Glass OptionsGlazing options available that meet fire code requirementsg p q1) Glass With Intumescent Interlayers (and similar gel-filled

products)2) C i Gl2) Ceramic Glass 3) Fire-Rated Framing Systems

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Fi R t d Gl Fi P t tiFire-Rated Glass: Fire-Protective Versus Fire-Resistant

Ceramic Fire-Rated: Fire-resistant but not fire-protective• Stops the direct expansion of fire but does not stop heat transfer• Can lead to spontaneous combustion of objects in protected areas• Ceramic products are listed for use in non-impact safety-rated locations and

are appropriate for applications ranging from 20 to 90 minutes.

Intumescent Fire-Rated: Both fire-protective and fire-resistantIntumescent Fire Rated: Both fire protective and fire resistant • Expand at about 250°F, transform into a rigid and opaque shield that blocks

both convected and radiated heat transmission • Listed for complete transparent non-load bearing wall assemblies up to 120 p p g p

minutesThis illustration demonstrates how intumescent interlayers

expand at about 250°F p

Fire-Rated Glass: Framing Systems

• Allow for through vision fire• Allow for through-vision fire protection

• Flexible framing solutions can include:include:

1) Wood, aluminum, or steel framing

2) Thermally broken framing for2) Thermally broken framing for transparent walls

3) Butt glazing (glass butted together, joined by virtually invisible silicone j y ysealant)

• Framing solutions can offer varying degrees of fire or safety protection,

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depending upon the glass products installed within them

Fi R t d GlFire-Rated Glass: Key Terminology

Integrity (E)—ability to prevent the passage of flames and hot gasesLow Radiation (EW)—ability to keep heat radiation below 15 KW/m2

on the protected side (measured from a one-meter distance)Insulation (EI)—ability to stop heat transfer on the protected side (maximum allowed Tº rise on the glass +285ºF average/350ºF locally)Internal Grade (IG)—suitable for internal applications not exposed to UV raysExternal Grade (EG)—suitable for external applications (facades) asExternal Grade (EG)—suitable for external applications (facades), as well as internal applications exposed to direct UV rays

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Insulating Glass: Designed for Energy Efficiency

• Two or more lites of glass assembled to created a hermetically sealed insulating spaceinsulating space

• Reduce heat gain/loss between interior and exterior spaces to improve energy efficiency

• Incorporate various glass types, coatings or tints depending uponcoatings, or tints depending upon requirements

• May also have high-performance

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spacer systems, insulating gas, decorative muntins and internal blinds

Purpose of the spacer

Insulating Glass: Spacer Options

• Provides structural integrity to maintain airspace between glazing litesAct as a carrier for the desiccant system• Act as a carrier for the desiccant system

• Act as the support system for sealantsPurpose of the spacer system (spacer, desiccant and sealants)Purpose of the spacer system (spacer, desiccant and sealants) within an IG unit

• Maintain space between glazing lites• Dry gas in space to prevent moisture condensation• Retain insulating gas fills within space• Maintain hermetic seal around IG perimeter

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• Maintain hermetic seal around IG perimeter

Insulating Glass:Insulating Glass: Gas Filling Options

• Inert insulating gases reduce conductive and convective heat transfer through IG unit.

• Argon is most common but may utilize krypton and othermay utilize krypton and other high performance gases for special applications

• Typically a percentage of gas content mixed with air

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I l ti Gl S i l F tInsulating Glass: Special Features• Muntins inside IG units simulate a true divided

lite without the labor and expense. A variety of shapes and colors are available.

I t l bli d d f li ht d h t t l• Internal blinds used for light and heat control also reduce cleaning and maintenance requirements.

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Spandrel Glass: Creating a

• Spandrel glass

Spandrel Glass: Creating a Seamless Appearance

• Spandrel glass conceals structural components such as floor and ceilingfloor and ceiling joists which would interfere with the seamless appearance spandrelof curtain wall facades

spandrel

• There are two types of spandrel glass -silicone coated and

i f it t d

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ceramic frit coated

Silk Gl C tSilkscreen Glass: Custom Aesthetics—and Solar Control

• Silkscreen designs provide a decorative, colored pattern on float or coated glass.

• Ceramic frit paint is silkscreened to glass substrate in a pattern of dots, lines, or holes then “fired” to becomes a durable permanent part of the glassbecomes a durable, permanent part of the glass.

• Silkscreen glass also acts to diffuse light and radiant heat transmission, thus providing solar control. p g

• Custom silkscreen colors and patterns can be specified, to create a truly one-of-a-kind effect.

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SECTION 4SECTION 4

Making the Right Glass ChoiceGlass Choice

Gl S l ti C it i

In specifying the best possible glass solution for each

Glass Selection Criteria

In specifying the best possible glass solution for each project, architects must consider a range of factors, including:

• Glass Aesthetics• Performance Needs• Application Demands• Product Considerations

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Choosing a Glass:Choosing a Glass: Aesthetic Considerations

• Unique aesthetic vision• Increasing demand for natural light• Selection of the glass substrate and color• Glass coatings (performance and aesthetics)• Fabricating options• Understanding of the design implications

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Ch i GlChoosing a Glass:Performance Needs

Consider long-term energy efficiency• Significantly impacted by glass choice• Daily comfort of those who will occupy the building• Daily comfort of those who will occupy the building

Maximize year-round energy performance

Invest in energy-efficient solutions (may be larger investment)Invest in energy-efficient solutions (may be larger investment)• Cutting edge technologies• Labor-intensive processes

Resources • International Energy Conservation Code (IECC)

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• Leadership in Energy and Environmental Design (LEEDTM) Green Building Rating System

IECC®: Mapping Performance Needs• IECC® prescribes energy performance requirements• IECC® prescribes energy performance requirements• Eight U.S. regions with patterns of annual heating/cooling demands• Glass and window products can be specified based upon their “fit”

for the region in which they will be installed

All of Alaska in Zone 7, except for

Zone 1 includes Hawaii, Guam,

Puerto Rico, and the Virgin Islands

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All of Alaska in Zone 7, except for the following Boroughs in Zone 8: Bethel, Dellingham, Fairbanks N. Star, Nome, North Slope, Northwest Arctic, Southeast Fairbanks, Wace Hampton, Yukon-Koyukuk

the Virgin Islands

E i “G ” D i LEEDTM

• LEEDTM Green Building Rating System has created guidelines

Encouraging “Green” Design: LEEDTM

g g y gand recommendations for specifying windows.

• Developed by the U.S. Green Building Council, LEED is designed to accelerate the development and implementation g p pof green building practices.

• LEED recognizes not only energy efficiency, but also indoor environmental quality—considering thermal comfort, as well q y g ,as ample daylight and views.

• In addition, LEED awards points for manufacturers’ recycling practices, and their proximity to job sites (decreasing p , p y j ( gtransportation impacts).

• Low-E windows and other innovative glass solutions are ideal for meeting LEED’s “green” building design criteria.

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g g g g

Ch i GlChoosing a Glass:Application Demands

• In addition to meeting building codes where hurricane resistance, security, or fire safety may be a concern, consider the everyday strength needs of the glass.

• Loads on architectural glass can include mechanical stresses (caused by high winds or snow accumulation) and thermal stresses (caused by heat build-up).thermal stresses (caused by heat build up).

• Vertical, sloped, overhead, and flooring installations include their own special set of concerns and product requirements Be cognizant of the extra strength andrequirements. Be cognizant of the extra strength and safety needs of glass installed in these applications.

• Also consider appropriate framing systems and glass

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sealants, which can lend structural support and longevity.

Ch i Gl

A il bl thi k i d f b i ti ti

Choosing a Glass:Understanding Product Considerations

• Available thicknesses, sizes, and fabricating options• Product customization does come with its costs

• It may make sense to choose standard glass sizes and y gfinishing options whenever possible.

• Partner with glass suppliers to balance creativity with practicality and cost effectiveness.practicality and cost effectiveness.

• Customized products can also take time• Understand the impact of specialized glass solutions on

th ll j t h d lthe overall project schedule.• Restrictions imposed by building codes

• Ensure that glass suppliers have conducted adequate

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Ensure that glass suppliers have conducted adequate product testing to ensure that their products meet these requirements.

S f Additi l I f tiFor more information, contact the following organizations:

A i A hit t l M f t A i ti t

Sources of Additional Information

• American Architectural Manufacturers Association, www.aamanet.org

• American Society for Testing and Materials International, www.astm.org

• Canadian Window and Door Manufacturers Association, www.cwdma.caCa ad a do a d oo a u actu e s ssoc at o , c d a ca

• Efficient Windows Collaborative, www.efficientwindows.org

• ENERGY STAR® program, www.energystar.gov/windows

• Glass Association of North America, www.glasswebsite.org

• International Energy Conservation Codes, www.energycodes.gov

• Insulating Glass Manufacturers Alliance www igmaonline org• Insulating Glass Manufacturers Alliance, www.igmaonline.org

• National Glass Association, www.glass.org

• National Fenestration Rating Council, www.nfrc.org

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• U.S. Green Building Council, www.usgbc.org

Course SummaryFollowing this course you should have an

• How glass is used in architectural applications—and the

Following this course, you should have an increased understanding of:

functionality and performance benefits it can provide• Different types of glass—and their applications• Fabricated glass solutions and their applications—includingFabricated glass solutions and their applications including

insulating units, heat-treated glass, and fire-rated glass • How to measure and evaluate glass performance—to make

better-informed choices when specifying glassbette o ed c o ces e spec y g g ass

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Thank you!This concludes the American Institute of Architects

C ti i Ed ti S t PContinuing Education System Program.

Are there any questions?y q

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S i E l tiSeminar EvaluationThank you for your kind attention. y y

Please take a moment to complete the evaluation formthe evaluation form.

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