Types of Exterior Glass
Beautiful and strong architectural products from AGC can be found in thousands of commercial buildings across North America. From office buildings, schools, and hospitals to shopping malls and airports, AGC’s broad, diverse family of exterior glazing solutions meets the highest aesthetic standards, while offering extraordinary performance. Advanced manufacturing capabilities enable AGC to produce a wide range of glass types to address the prevailing commercial building needs, including light transmission, solar control, wind resistance, safety, security, and year-round energy efficiency.
Soft Coat Low-E Glass
AGC applies “soft” or sputter coatings by subjecting float glass to extremely low pressures in a vacuum chamber and using a sophisticated process to deposit specific metal atoms onto the glass surface. The unique combination of atoms determines the ultimate performance properties of each AGC Low-E glass solution.
Unlike pyrolytic coatings, sputter coatings are applied to the suface of the glass after the float process. For this reason, they are considered “soft” coatings. However, sputter coatings deliver a wide range of benefits. These coatings can be applied to any glass substrate, covering the full range of performance and aesthetic requirements.
AGC’s sputter-coated products also feature post-temperable technologies that allow them to be heat treated and laminated for special customer applications.
Since its introduction, the Comfort Ti™ soft-coat product family has become an established industry leader in innovation and energy efficiency—setting new standards for year-round comfort, energy savings, visible light transmittance, and color neutrality. AGC offers a Comfort Ti solution for every ENERGY STAR® region in North America—as well as products designed specifically for commercial buildings and private residences.
AGC's brand of high performance Low E soft coat products deliver outstanding performance in any application
Hard Coat Low-E Glass
With a durable Low-E coating applied during the float manufacturing process—becoming an integral part of the glass—AGC’s hard-coat (pyrolytic) products are tough enough to withstand the real-world demands of glass transportation and handling. Hard-coat products are also easy to stack, store, and fabricate—and they stand up exceptionally well to such special processes as tempering, laminating, and insulating. Hard-coat products from AGC do not require edge deletion when assembled in an IG unit. AGC offers two hard-coat solutions: Comfort E-PS™, which can be used both in residential and commercial applications, and Sunergy®, which is designed specifically for the commercial market.
Versatile float glass products from AGC can be processed in many ways for use in numerous applications, including construction, decoration, automotive, and high-tech industries. AGC float products offer many benefits, such as perfectly flat and parallel surfaces, high levels of transparency and light transmission making them an excellent base for further processing. Float glass substrates can be used for coatings, single glazing, insulating glazing, laminating, tempering, enameling, silk screening, sandblasting, bending and many other operations.
AGC’s Stopsol® hard-coated glass is an attractive choice when a reflective appearance is part of the architectural vision. Available in Clear, Green, Grey, Bronze, and Blue substrate colors, this innovative glass combines a beautiful reflective appearance with excellent solar control properties—in a range of thicknesses to meet a spectrum of architectural and performance needs. The Stopsol family offers three coating options: Classic (amber look), Supersilver (silvered look), and Silverlight (bluish look). A variety of substrate colors and coating options are also available, offering architects a highly customized look. Additionally, Stopsol can be applied to Matelux® acid-etched glass to achieve a unique aesthetic effect.
Each Stopsol offering provides a unique combination of benefits, including high levels of light transmission, low heat absorbency, and customized levels of reflectance for enhanced privacy and the visual comfort of building occupants. Stopsol can be laminated, bent, and used both monolithically and as part of an insulating unit. Stopsol can also be combined with other AGC products in an IG unit to deliver custom-tailored energy performance that meets specific regional needs. A pyrolytic “hard-coat” product, Stopsol offers worry-free transportation, handling, and fabrication.
An insulated glass unit is factory sealed and consists of multiple lites of glass separated by a spacer and filled with dehydrated air and/or gas. The main purpose of double or triple glazing is to provide a higher level of thermal insulation than single glazing. The thermal insulation characteristics of insulated glazings can be combined with properties such as solar control, sound insulation, and safety by using the appropriate glass products as components of insulated glazing.
The first type of thermally insulating glazing was double glazing, which is composed of two sheets of glass separated by a spacer to provide a space filled with dry air. Since the air has a thermal conductivity of 0.025 W/(m.K) (at 50˚F or 10˚C), while that of glass is 1 W/(m.K), the layer of air enhances the insulating properties and reduces the U Factor of the glazing.
High Performance Double Glazings
The development of techniques for applying metallic coatings to glass has been a decisive step forward in improving the thermal insulation of glazings. Applying a metallic coating to a glass makes it “high- performance” (also called “low-emissivity” or “low-E”). These coatings generally fall into two categories; “soft” or Sputter coatings and “hard” or Pyrolytic coatings. In a double glazing with glass surfaces numbered 1 through 4, low-E coatings are generally applied in position 2 or 3.
A laminated glass is an assembly composed of at least two panes of glass bonded together across their entire surface by an interlayer. For laminated safety glass, the most widely used interlayer is a plastic PVB (polyvinyl butyral) film, but EVA (ethylene vinyl acetate) films or a safety resin may also be used. In the event of breakage, the bond between the glass and the interlayer ensures that the broken pieces remain in place—at least for a certain period or up to a specified load level.
According to standard ANSI Z97.1, a laminated glass may be considered a safety glass if it meets the requirements of a specific resistance class following the pendulum impact test detailed in this standard. Laminated glass may be annealed, heat-strengthened or tempered and may be used monolitically or as part of an insulated glass unit. Tempering provides mechanical strength, while heat-strengthening gives adequate residual stability if the glass breaks and cannot be immediately replaced. Heat-strengthened laminated glass is sometimes used when a higher level of wind load resistance is required than that offered by annealed float glass—as well as to prevent the risk of breakage due to thermal shock
Laminated Glass Options
Spandrel panels are positioned on the exterior of commercial buildings to mask opaque sections, as well as the structural elements of facades. Used in conjunction with vision glazings, they have given rise to “curtain wall“ facades. Depending on the products and colors used, either complete harmony or contrasting effects can be achieved when specifying spandrels and vision glass. From an aesthetic point of view, choosing the ideal spandrel for a particular vision glazing is not always easy. AGC recommends that architects, specifiers, building owners, and glass professionals work together to choose the most appropriate solution, using actual glass samples and prototypes. AGC has an expert team of Architectural and Technical Services consultants to support this decision-making process. Spandrels can be combined with thermal insulation, sound insulation, and fire protection functions, depending on the specific customer application.
A number of different types of spandrels are available:
- Single-pane, ceramic frit enameled glass—this is clear or colored glass that is coated with a ceramic frit and then tempered or heat strengthened
- An insulating glazing made of the same glass as vision glass (as an external glass) and spandrel glass (as an internal glass)
- An insulating glazing enameled in position 4
- A shadow-box—this is a spandrel made up of vision glazing combined with an opaque background (metal sheet, etc.) in order to produce an opaque glass section in harmony with the building
Spandrels are heat strengthened or tempered, except in special cases in which a preliminary study has been carried out.