Task Group Approval

Out for ballot #20-1001

Committee/Council Approval

Technical Steering Committee

Approval

AAMA PSSG-XX DRAFT #1

DATED 01/09/20

Selection and Application Guide for Plastic Glazed Skylights and Sloped Glazing

This document was developed by representative members of FGIA as advisory information and published as a public service. FGIA disclaims all liability for the use, application or adaptation of materials published herein.

© Copyright 2020 Fenestration & Glazing Industry Alliance

Email: publications@fgiaonline.org Website: https://fgiaonline.org/

AAMA PSSG-XX, DRAFT #1, DATED 1/9/20 PAGE i

TABLE OF CONTENTS

0.0 INTRODUCTION .......................................................................................................................................... 1 1.0 SCOPE ........................................................................................................................................................... 1 2.0 REFERENCED STANDARDS ...................................................................................................................... 2 3.0 DEFINITIONS ................................................................................................................................................ 4 4.0 DESIGN AND AESTHETIC OPPORTUNITIES ......................................................................................... 4 5.0 SKYLIGHT AND SLOPED GLAZING DESIGN FOR PLASTIC GLAZING ............................................. 7 6.0 FUNCTIONAL PERFORMANCE REQUIREMENTS ................................................................................. 8 7.0 PLASTIC PROPERTIES AND ATTRIBUTES .......................................................................................... 11 8.0 CODES AND REGULATORY CONSIDERATIONS ................................................................................ 12 9.0 CARE AND MAINTENANCE OF PLASTIC GLAZED SKYLIGHTS AND SLOPED GLAZING .......... 13

AAMA PSSG-XX, DRAFT #1, DATED 1/9/20 Page 1

0.0 INTRODUCTION

This document is part of a suite of documents generated to educate interested parties in the proper design, selection,

specification and use of skylights. The reader is encouraged to explore all the skylight publications for a complete

understanding of the properties associated with skylights. Below is a list of all current AAMA skylight documents.

• AAMA SDGS-1-89, Structural Design Guidelines for Aluminum Framed Skylights

• AAMA 1607-14, Voluntary Installation Guidelines for Unit Skylights

• TIR A7-11, Sloped Glazing Guidelines

• AAMA SSGPG-1-17, Structural Silicone Glazing (SSG) Design Guidelines

• AAMA GDSG-1-87, Glass Design for Sloped Glazing and Skylights

1.0 SCOPE

1.1 The purpose of this document is to provide the architect, engineer, contractor and property owner with the information

and knowledge to understand the value and effective application of plastic glazed skylights and sloped glazing in a building

design as well as the features and benefits of different plastic glazing materials (see examplfigures 1-4).

Plastic glazed skylights and sloped glazing can be used to provide significant energy savings and enhance the aesthetic

appearance of a building as well as the appeal of its interior spaces, flooding them with the warmth and illumination of

natural daylight. This document will provide the guidance to best leverage their advantages by giving sound technical

information on the various aspects and considerations that need to be taken into account when applying plastic-glazed

skylights and sloped glazing as an enhancement to a building design. The plastics referred to are “thermoplastic” materials

such as polycarbonate, co-polyester, acrylic and not “thermoset” materials such as fiberglass reinforced polymer. It should

be emphasized that the chosen skylight manufacturer should be consulted, in combination with this document, as the

primary resource for answering questions and for providing technical assistance regarding their products.

FIGURE 1: Vaulted

Skylight

FIGURE 2: Daylit School

FIGURE 3: Complex Curved

Vault

FIGURE 4: Polygon

AAMA PSSG-XX, DRAFT #1, DATED 1/9/20 Page 2

1.2 The primary units of measure in this document are I.P. The values given in parentheses are for reference only.

1.3 This document was developed in an open and consensus process and is maintained by representative members of

AAMAFGIA as advisory information.

2.0 REFERENCED STANDARDS

2.1 AAMA, Fenestration and Glazing Industry Alliance (FGIA) Standards

AAMA/WDMA/CSA 101/I.S.2/A440-05, Standard/Specification for Windows, Doors, and Unit Skylights

AAMA/WDMA/CSA 101/I.S.2/A440-08, North American Fenestration Standard/Specification for windows, doors, and

skylights

AAMA/WDMA/CSA 101/I.S.2/A440-11, North American Fenestration Standard/Specification for windows, doors, and

skylights

AAMA AG-13, AAMA Glossary

Skylight Glossary of Terms

2.2 ASCE/SEI (American Society of Civil Engineers/Structural Engineering Institute)

ASCE/SEI 7-16, Minimum Design Loads for Buildings and Other Structures

2.3 American Society for Testing and Materials (ASTM)

ASTM D256-10(2018), Standard Test Methods for Determining the Izod Pendulum Impact Resistance of Plastics

ASTM D635-18, Standard Test Method for Rate of Burning and/or Extent and Time of Burning of Plastics in a Horizontal

Position

ASTM D638-14, Standard Test Method for Tensile Properties of Plastics

ASTM D790-17, Standard Test Methods for Flexural Properties of Unreinforced and Reinforced Plastics and Electrical

Insulating Materials

ASTM D792-13, Standard Test Methods for Density and Specific Gravity (Relative Density) of Plastics by Displacement

AAMA PSSG-XX, DRAFT #1, DATED 1/9/20 Page 3

ASTM D1003-13, Standard Test Method for Haze and Luminous Transmittance of Transparent Plastics

ASTM D1929-16, Standard Test Method for Determining Ignition Temperature of Plastics

ASTM D2843-16, Standard Test Method for Density of Smoke from the Burning or Decomposition of Plastics

ASTM D3763-18, Standard Test Method for High Speed Puncture Properties of Plastics Using Load and Displacement

Sensors

ASTM D6110-188, Standard Test Method for Determining the Charpy Impact Resistance of Notched Specimens of

Plastics

ASTM E84-18b, Standard Test Method for Surface Burning Characteristics of Building Materials

ASTM E2387-05(2011), Standard Practice for Goniometric Optical Scatter Measurements

ASTM G155-13, Standard Practice for Operating Xenon Arc Light Apparatus for Exposure of Non-Metallic Materials

2.3 American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE)

ASHRAE 90.1-2013, Energy Standard for Buildings Except Low-Rise Residential Buildings

2.5 California Building Energy Efficiency Standards

CEC-400-2012-004-CMF-REV2, 2013 Building Energy Efficiency Standards for Residential and Nonresidential Buildings

2.56 Illuminating Engineering Society

LM-81-10, Photometric Testing of Skylights and Tubular Daylighting Devices under Hemispherical Sky Conditions

2.78 International Code Council (ICC)

2015 International Building Code (IBC)

2015 International Energy Conservation Code (IECC)

2015 International Residential Code (IRC)

8 Underwriters Laboratories (UL)

AAMA PSSG-XX, DRAFT #1, DATED 1/9/20 Page 4

UL 723 (Edition 10), Standard for Test for Surface Burning Characteristics of Building Materials

3.0 DEFINITIONS

Please refer to the most current AAMA Glossary (AG-13) and the AAMA Skylight Council Glossary for all definitions except

for those appearing below (which apply only to this document).

Aerogel: A light transmitting, nanoporous silica derived from a gel, in which the liquid component of the gel has been

replaced with a gas. A synthetic porous material characterized by hydrophobicity (highly water repellent) and ultra-low

thermal conductivity, used as filler in architectural glazing.

4.0 DESIGN AND AESTHETIC OPPORTUNITIES

4.1 Configuration of Products for Performance

Plastic glazing in skylights and sloped glazing provides unique aesthetic and functional opportunities to the architect

seeking daylighting solutions for their project. There are examples below in Figures 5-8. The ability to incorporate a variety

of three- dimensional shapes such as curved surfaces, polygons, pyramids and others can add desirable form to the

exterior of a building while optimizing natural light gathering and light distribution performance as a direct result of the

inherent formability of plastic glazing.

The ability to create a variety of shapes (curved barrel vaults, domed, pyramid, fluted, etc.) adds structure and inherent

water- and snow- shedding characteristics. This produces structural attributes that are particularly important on low slope

and flat roof applications. Since many natural daylighting/top-lighting applications are in buildings with low slope roofs,

plastic glazed skylights and sloped glazing are particularly suited for this task.

AAMA PSSG-XX, DRAFT #1, DATED 1/9/20 Page 5

FIGURE 5: Fluted Unit Skylight

FIGURE 6: Barrel Vault Skylight

FIGURE 7: Faceted Skylight

FIGURE 8: Domed Skylight

AAMA PSSG-XX, DRAFT #1, DATED 1/9/20 Page 6

FIGURE 9: Skylight Cross Section with Multiple Glazing Layers

The combination of multiple glazing layers can provide a broad performance range. The exterior layer can shed unwanted

heat gain, can be designed to optimize light gathering, and must perform the critical structural work of resisting wind loads,

snow loads and certain impact loads. The interior layers can enhance insulating performance and light distribution within

the space, see figure 9.

4.2 Glazing Material Properties

Plastic glazing material can provide light diffusion properties delivering high light quality, and well distributed soft natural

light for a pleasant and functional interior environment. Glazing formability can yield a variety of shapes that can gather

light at low sun angles and improve light distribution within the space. Texturing the plastic glazing surface can further

enhance light gathering and distribution performance, such as prismatic patterns embossed on the sheet surface.

Multiwall plastic glazing, see figure 11, is produced in many profile configurations which can improve thermal performance

while maintaining a balance with light transmission. Multiwall sheet can also deliver enhanced structural characteristics.

This can be further improved when it is cold or heat formed into a configuration such as a barrel vault. Multiwall sheet can

also be filled with material such as aerogel which further enhances thermal performance without significant loss of visible

transmittance.

AAMA PSSG-XX, DRAFT #1, DATED 1/9/20 Page 7

Spectrally selective modifications in the form of additives or coatings minimize or virtually eliminate ultraviolet (UV) and

infrared (IR) portions of the light spectrum, see figure 10. UV exposure can cause fading and damage to furnishings, fabrics,

artwork and other interior treatments, and affect human health with high exposure. IR radiation is the cause of solar heat

gain which can increase air conditioning load.

5.0 SKYLIGHT AND SLOPED GLAZING DESIGN FOR PLASTIC GLAZING

Plastic glazing provides some product design considerations that are important to understand. Product manufacturers are

experts in this regard. It is valuable for the designer, installer and contractor to also understand these principles.

5.1 Frame Design Considerations

The practice of using plastic glazing in framing systems designed specifically for glass is usually not recommended. Plastic

glazing has a high thermal expansion rate. This requires the framing system to provide an adequate depth (glazing bite) at

the edges of the glazing; this depth will accommodate the movement and the sealing of the product at the frame/glazing

interface allowing the glazing to move while maintaining a good seal. Weather-seals/gaskets can be used that are

mechanically fixed or secured to the frame allowing the plastic to move on the sealing elements without compromising the

effectiveness of the seal for air and water infiltration, see figure 12. .Some tape seals of proper design can be utilized for

this purpose while wet seals are generally not recommended due to the significant movement of the plastic sheets in

relation to other materials in the design.used. This is particularly important for field applied sealants.

Although some skylight manufacturers have had success with wet sealants, extreme caution should be used when using

wet sealants with plastic glazing due to the significant movement of the plastic sheets in relation to other materials in the

design. This is particularly important for field applied sealants.

Figure 10: Monolithic Plastic Sheets

Figure 11: Multiwall Plastic Sheets

AAMA PSSG-XX, DRAFT #1, DATED 1/9/20 Page 8

Figure 12X: Skylight Cross Section

An advantage of plastic glazing’s inherent flexibility is that it is more forgiving of the movement/deflection of the framing

systems. This can allow for lighter framing that can handle structural loads effectively with less weight and cost.

5.2 More Seal Considerations

Compatibility of all the materials coming into contact with the plastic glazing is critically important. This includes but is not

limited to gaskets, sealants, tape seals and cleaners.

Airspaces between layers of plastic glazing are different than “hermetically sealed” airspaces in insulating glass unit (IGU)

construction. Plastic glazing allows for the passage of water vapor through the sheet. The sealing of the sheet materials on

the edges must account for this fact. The purpose of edge sealing in this case is to eliminate dust and excessive air

infiltration exchange between the interior airspace and exterior environment. There are at least two common ways to

accomplish this; the use of properly formulated and designed tape seals, or dry gasket seals.

Multiwall sheet materials are often tape sealed on the top edge and filter taped on the bottom edge. Interior support walls

should be running downwards to provide a water drainage path eliminating the possibility of trapped water within the

sheets.

Sealing of the edge of the airspace must be designed to accommodate the thermal expansion and contraction of the sheet,

and any expected differences in the movement of the glazing layers. The seal design must ensure that water is not trapped

between layers.

6.0 FUNCTIONAL PERFORMANCE REQUIREMENTS

AAMA PSSG-XX, DRAFT #1, DATED 1/9/20 Page 9

Skylights and sloped glazing are subject to many applicable standards. The main product performance standard,

referenced in many building codes, that covers unit skylights is AAMA/WDMA/CSA101/I.S.2/A440 (NAFS). There are also

material performance requirements relative to strength, durability, flammability and weathering properties.

NAFS contains the requirements for plastic glazing materials. Plastics must be rated for flammability properties. Plastics,

including thermoplastic, thermosetting or reinforced thermosetting plastic material must meet three flammability

requirements:

1. They must have a self-ignition temperature of 650°F (343°C) or greater when tested according to ASTM D1929.

2. A smoke-developed index not greater than 450 when tested according to ASTM E84 or UL 723, or a maximum

average smoke density rating not greater than 75 when tested to ASTM D2843.

3. Additionally, plastics must conform to either one of the following combustibility classifications:

a. Class CC1: Plastic materials that have a burning extent of 1 inch (25 mm) or less where tested at a

nominal thickness of 0.060 inch (1.5 mm), or in the thickness intended for use, in accordance with ASTM

D635 or;.

b. Class CC2: Plastic materials that have a burning rate of 2 1/2 inches per minute (1.06 mm/s) or less

where tested at a nominal thickness of 0.060 inch (1.5 mm), or in the thickness intended for use, in

accordance with ASTM D635.

Plastic glazing materials must also meet the durability and weathering requirement of Clause 10 of NAFS. Plastics can be

evaluated for weathering using either ASTM G155 Xenon Arc accelerated testing or five-year South Florida real time

testing. Plastic glazing materials must not change more than 10% in haze when measured according to ASTM D1003. They

must also retain a degree of toughness which is determined by either ASTM D6110 Charpy Impact or ASTM D638 Tensile

Strength. Maintaining optical clarity over time may require additional abrasion resistance. Abrasion resistant coatings are

available for these applications. Coatings and coextruded layers can also be added to the plastic sheet materials to enhance

weathering performance and retention of color or optical properties.

Impact modified acrylic, polycarbonate and co-polyester can provide resistance to damage from wind-borne debris, in

applications that warrant large missile impact testing. These plastic glazing materials stay intact, and in most cases, they

generally remain in place through the conclusion of the cycling phase of the test. An important design element in such

applications is good frame-to-glazing clamping/retention design and the product’s design as a whole contributes to

achieving the required performance.

When used in an appropriately designed skylight, impact modified acrylic, polycarbonate and co-polyester material types

can be suitable for anti–terrorism blast resistant applications. The U.S. Department of Defense (D.O.D.), U.S. General

Services Administration (GSA) and other ISO test methods specify testing protocols and performance standards. As for

wind-borne debris requirements, good frame-to-glazing clamping/retention design is important such that the product’s

design as a whole can handle the required performance aspects.

AAMA PSSG-XX, DRAFT #1, DATED 1/9/20 Page 10

Plastic glazed skylights and sloped glazing can also address challenges of hail resistance and, burglary resistance and

human impact resistance. They can also contribute to control of sound transmission.

CAUTIONARY NOTE 1: After any extreme weather or blast event, skylights should be examined for structural integrity.

AAMA PSSG-XX, DRAFT #1, DATED 1/9/20 Page 11

7.0 PLASTIC PROPERTIES AND ATTRIBUTES There are a number of plastic materials available that are well suited for skylight glazing. Each one provides its own set of attributes that can meet the specific requirements of the application. The materials covered in Table 1 have demonstrated their ability to perform in skylight applications. As in any material selection the use of products from a trusted manufacturer that can verify the performance of their materials and the quality of their product with testing, a strong quality assurance program and a proven track record are important considerations. The basic material types are as follows:

Acrylic Impact Modified

Acrylic Co-polyester Polycarbonate

Uniform Load Resistance

Rigid dome structure, can

achieve high static

pressures

Semi-rigid dome structure, can

achieve relatively high static

pressures

Flexible dome structure, suitable

for moderate static pressures

Flexible dome structure, suitable

for lower static pressures. Higher

pressures achieved with ‘ribs’ or

other geometries in dome shape

Ductility

Formability Specific Gravity per ASTM D792 (g/cc) 1.19 1.16 1.23 1.2

Yield Tensile Strength per ASTM D638

(Mpa)

69 46.2 48 62

Elongation at yield per ASTM D638 (%) -- 6.6 5 --

Tensile Modulus per ASTM D638 (Mpa) 3400 2203 1800 2300

Break Tensile Strength per ASTM D638

(Mpa)

69 46.2 53 65

Elongation at Break per ASTM D638 (%) 4.5 -- 340 110

Flexural Strength per ASTM D790 (Mpa) 117 82.7 71 93

Flexural Modulus per ASTM D790 (Mpa) 3300 2066 2000 2400

Impact Resistance

Rigid material acts brittle

when impacted

Semi-rigid material acts a bit brittle

when impacted

Soft and flexible material

absorbs impacts well

Soft and flexible material absorbs

impacts very well

Izod Impact per ASTM D256 (notched)

(J/m)

22 39.4 NB 936

Izod Impact per ASTM D256 (unnotched)

(J/m)

22 -- NB @ 23oC NB

Instrumented impact per ASTM D3763 (J) -- -- 41 > 45

Optical Clarity

Best clarity achieved due

to cast production method

Minor clarity loss due to extrusion

process

Minor clarity loss due to

extrusion process & some loss

due to softness of material

Minor clarity loss due to extrusion

process & some loss due to

softness of material

Light Transmission (%) 92.0 91.0 91 86

Weatherability Xenon Arc 5-yr Weathering % Loss in Light

Transmission per ASTM D1003 0.5 0.4 1 1

Xenon Arc 5-yr Weathering % change in

Tensile Strength per ASTM D638 3-5 -- Up to 8% Up to 7.5%

Xenon Arc 5-yr Weathering Yellowness

Index per ASTM D1925 0.5 0.5 3 2

Flame Spread Horizontal burn per ASTM D635 CC2 CC2 CC1 CC1

Self Ignition Temperature per ASTM

D1929 oC (oF)

454 (850) 399 (750) 443 to 460 (830 to 860) 466 (870)

Smoke Density per ASTM D2843 10% 3.8% < 75 % < 75 %

AAMA PSSG-XX, DRAFT #1, DATED 1/9/20 Page 12

TABLE 1: Relative Attributes of Plastic Glazing Materials

Each material type has a range of formulations, additives, coatings and processing methods that can affect and enhance

these basic properties. The tables provided are a guideline. It is important to understand that it is the combination and

balancing of these properties that optimizes the performance attributes to best meet the demands of a specific application.

The manufacturer can provide this guidance.

NOTE 2: Refer to the Appendix for typical measured properties of plastic glazing materials. These values are the source

of information for the relative attributes of plastic glazing materials table.

Plastic glazing materials, in order to be deemed suitable for use as a skylight glazing material, must meet various

performance criteria as specified in the International Building Code (IBC) and NAFS regarding skylights and sloped glazing

and “Light Transmitting Plastics.” All materials can be provided in tints by introduction of color pigments for the purpose

of reducing Visible Transmittance (VT) & Solar Heat Gain Coefficient (SHGC) performance, as well as for aesthetic

concerns. Colors such as bronze and grey achieve this while retaining good vision and optical clarity. These tinted

transparent products do not appear to be tinted when viewed from the interior during daylight hours or at night. Translucent

pigmented products (typically white) provide greater solar control and reduction in VT. Translucent white provides no view

through the material; however, it creates good light diffusion and distribution while reducing or eliminating glare from direct

sunlight, providing the best overall light quality. For the building designer the dramatic effect of the sun moving across the

sky and the constant changing interior aesthetic may be more desirable. The purpose of the interior space will dictate

these design considerations. Contact with the outside environment is better achieved with tinted transparent glazing if that

is the effect the designer is seeking.

If the designer’s purpose is more driven by the need to deliver functional task lighting into the interior space, then factors

such as good light distribution and task lighting quality dictate translucent materials for their light diffusion properties. The

haze value measured to ASTM D1003 has historically been used to quantify light diffusion for skylight applications. The

method has advantages of being simple, inexpensive and readily available, but it was developed for materials with < 30%

haze and therefore does not differentiate diffusion performance of glazing layers with moderate to high levels of diffusion.

Methods such as ASTM E2387 exist to measure the light diffusion of a translucent plastic. Such methods are able to more

accurately assess and compare a plastics’ ability to scatter and distribute the transmitted light, especially at higher diffusion

levels. In light of this, the industry continues to seek better methods of evaluating light diffusion performance.

When detailed light distribution information is required for top-lighting products with complex glazing layers, additional

detailed test methodologies do exist such as IES LM-81-10. This test is designed to provide detailed light distribution data

for the purpose of daylighting design.

8.0 CODES AND REGULATORY CONSIDERATIONS

8.1 General

AAMA PSSG-XX, DRAFT #1, DATED 1/9/20 Page 13

Additional requirements related to the physical properties and weathering performance of plastic glazing materials are

outlined in the Model Codes developed by the ICC.

Skylights and sloped glazing are primarily covered in the International Building Code (IBC) Sections 1505.1, 1709.6, 2405,

2606 and 2610, and the International Residential Code (IRC) Section R308.6, with ancillary provisions in other sections.

Skylights and sloped glazing must meet the appropriate structural requirements of the roof including environmental loads

per ASCE/SEI 7 such as wind loads, snow load, etc.

Building energy codes also contain extensive provisions that constrain the designer to certain performance limits of both

the products and the buildings in which they are installed. The most influential ones in the US are:

• International Energy Conservation Code (IECC) – all building types

• ASHRAE 90.1 – Non-residential and high-rise residential

• California Building Energy Efficiency Standards, Title 24, Part 6 – all building types

We note also that an increasing number of projects are also being asked to conform to one of many available “sustainability”

or “green” codes, programs, checklists, standards, etc. Since there is much diversity, fluidity, and variety in those additional

“above code” requirements, this document will only concentrate on generally accepted constraints.

9.0 CARE AND MAINTENANCE OF PLASTIC GLAZED SKYLIGHTS AND SLOPED GLAZING

Plastic skylight glazing, with proper care and maintenance, can be kept clean and good-looking for many years. A clean

skylight will allow more light transmission than a dirty one and will look better when viewed from above and below. Specific

guidelines from the skylight manufacturer provide the most reliable information for the exact plastic material used in their

product, and if available should be used before generic instructions are followed.

To clean plastic skylight glazing, first rinse with warm water then apply a solution of a mild detergent and water with a soft

cloth and rinse well with water. To avoid water spots, blot dry with a chamois.

Plastic glazing is susceptible to scratching, abrasion and/or damage, such as crazing, by certain solvents and cleaning

chemicals. For advice on how to remove foreign material such as protective paper, glazing compound, caulking, roofing

tar, grease or fresh oil paint contact the skylight manufacturer.

• Do not use scrapers, squeegees or razors.

• Do not use abrasives, abrasive pads, paper towels or high alkaline cleaners.

• Do not leave cleaners on sheet for long periods, wash immediately.

• Do not apply cleaners in direct sunlight or at elevated temperatures.

AAMA PSSG-XX, DRAFT #1, DATED 1/9/20 Page 14

• Do not clean with gasoline, denatured alcohol, acetone or carbon tetrachloride.

All plastics should be cleaned periodically. A regular, once-a-year cleaning program will help prevent noticeable weathering

and dirt build-up.

Care and maintenance of your skylight(s) must be done with a priority on safety. Personnel performing these tasks should

be professionals trained in all aspects of roof safety and should be wearing the appropriate fall protection and personal

protective equipment. Skylights and sloped glazing are designed to withstand typical environmental conditions. Skylights

and sloped glazing are not intended to withstand human impact or falling objects. While some skylights and sloped glazing

are more impact resistant than others caution must be exercised when near them and they should never be walked on or

be used to support human body weight.

AAMA PSSG-XX, DRAFT #1, DATED 1/9/20 Page 15

APPENDIX A:

Property Test Method Units

Material

Acrylic Impact

Modified

Acrylic

Copolyester Polycarbonate

Specific Gravity ASTM D792 g/cc 1.19 1.16 1.23 1.2

Yield Tensile Strength ASTM D638 Mpa 69 46.2 48 62

% Elongation at yield ASTM D638 % 6.6 5

Tensile Modulus ASTM D638 Mpa 3400 2203 1800 2300

Break Tensile Strength ASTM D638 Mpa 69 46.2 53 65

% Elongation at break ASTM D638 4.5 340 110

Flexural Strength ASTM D790 Mpa 117 82.7 71 93

Flexural Modulus ASTM D790 Mpa 3300 2066 2000 2400

Izod Impact Strength

(notched)

ASTM D256 J/m 22 39.4 NB 936

Izod Impact Strength

(unnotched)

ASTM D256 J/m 22 NB @ 23 C NB

Instrumented impact ASTM D3763 J - 41 > 45

Horizontal burn ASTM D635 CC2 CC2 CC1 CC1

Self Ignition Temperature ASTM D1929 F 850 750 830 to 860 870

Smoke Density ASTM D2843 10% 3.8

(6mm)

< 75 % < 75 %

% Light Transmission ASTM D1003 % 92.0 91.0 91 86

Xenon Arc 5-yr Weathering %

Loss in Light Transmission

ASTM D1003 % 0.5 0.4 1 1

Xenon Arc 5-yr Weathering %

change in Tensile Strength

ASTM D638 % 3-5 Up to 8% Up to 7.5%

Xenon Arc 5-yr Weathering

Yellowness Index

ASTM D1925 YI 0.5 0.5 3 2

TABLE A1: Typical Properties of Plastic Glazing Materials

NOTE A13: Values above may be for different thicknesses and different manufacturers and values are not

considered directly comparable because thicknesses may vary.