Types of Architectural Glass Used in Construction
Architectural glass has transformed modern construction, offering unparalleled versatility, functionality, and aesthetics. Architects and contractors use various types of glass to enhance safety, thermal performance, and the visual appeal of buildings.
Novum Structures provides engineering solutions for these applications, supporting architects. This article delves into the types of architectural glass used in construction, their properties, and their applications.
Use and Structure of Architectural Glass
Glass is manufactured with different physical properties depending on its purpose. Several types of glass in construction vary based on safety, thermal performance, climate, and the visual appearance of the buildings. This post will explain the myriad of glass types so you can decide what best suits your building needs.
Base Glass – Tempered/Toughened Glass – Heat Strengthened Glass – Laminated Glass – Glass with Ceramic Frit – Low Iron Glass – Body Tinted Glass – Insulated Glass
Base Glass
Base glass consists of annealed float glass and ornamental glass. Float glass is the most basic glazing available internationally, making up to 90% of the base glass.
Float Glass Production Process
- A steady stream of molten glass is poured from a furnace into a shallow bath of molten tin.
- The glass floats on the tin, forming a flat surface as it cools.
- Rollers stretch the glass, creating thinner sheets with consistent dimensions.
This process ensures high-quality structural glass with excellent clarity and uniformity.
Specifications
- Maximum Dimensions: 6.0 × 3.2 meters
- Standard Thicknesses: 4, 5, 6, 8, 10, 12, 15, and 19 mm
- Breaking Strength: 45 N/mm²
Applications
Float glass is widely used for:
- Facades
- Interior partitions
- General glazing needs
Its simplicity and adaptability make it a primary choice for foundational glass structures. The float glass process produces high-quality structural glass for construction purposes.
Tempered Glass (Toughened Glass)
Tempered glass is a high-strength, safety-focused material that is approximately 2.5 times stronger than standard glass of the same thickness. This strength makes it ideal for demanding structural applications.
Production Process
- The glass is heated uniformly to a high temperature.
- It is then rapidly cooled, creating surface compressive stress and tensile stress in the core.
- This balance of stresses prevents microcracks from expanding, significantly enhancing durability.
Specifications
- Maximum Dimensions: 4.0 × 2.4 meters
- Standard Thicknesses: 4, 5, 6, 8, 10, 12, 15, and 19 mm
- Breaking Strength: 120 N/mm²
Safety Features
When tempered glass breaks, it shatters into small, blunt fragments, minimizing the risk of injury. This property makes it a preferred choice for safety-critical applications.
Applications
Tempered glass is widely used in:
- Balustrades and Handrails: Provides robust support while maintaining a sleek aesthetic.
- Fire-Resistant Doors: Offers thermal resistance and strength.
- Escalator Side Panels: Ensures safety in high-traffic areas.
- Airport Viewing Areas: Combines durability and clarity for public spaces.
- Structural Glass Elements: Withstands wind, snow, thermal, and seismic loads.
Its combination of strength and safety makes tempered glass essential for modern architectural projects.
Sea-Tac International Airport Project
Heat Strengthened Glass
Heat-strengthened glass is 1.5 times stronger than annealed float glass, enhancing its strength compared to standard glass. Thus, it offers a balance of durability and flexibility for various structural applications.
Production Process
- Heat-strengthened glass undergoes a thermal treatment similar to tempered glass.
- However, the cooling process is slower, resulting in lower surface compressive stress.
Specifications
- Maximum Dimensions: 4.0 × 2.4 meters
- Standard Thicknesses: 6, 8, 10, and 12 mm
- Breaking Strength: 70 N/mm²
Features
- Produces larger fragments upon breaking, which is beneficial for certain laminated glass applications.
- Provides additional strength for structural elements but is not classified as safety glass unless laminated.
Applications
Heat-strengthened glass is used in buildings requiring enhanced durability to withstand:
- Wind Loads: Ideal for areas with high wind pressure.
- Snow Loads: Ensures structural integrity in colder climates.
- Thermal Loads: Reduces risks associated with temperature fluctuations.
- Seismic Loads: Adds resilience in earthquake-prone regions.
This glass is often incorporated into curtain walls, laminated glass units, and other architectural features where strength and post-breakage performance are critical.
Laminated Glass
Laminated glass consists of two or more glass sheets bonded together by interlayers of polyvinyl butyral (PVB) or ionoplast materials. This layered structure enhances strength and safety, making laminated glass an essential choice for applications requiring durability and impact resistance.
Production Process
- Multiple glass sheets are bonded with interlayers to form a single unit.
- Interlayers, such as PVB, come in standard thicknesses of 0.38, 0.76, and 1.52 mm.
Specifications
- Maximum Dimensions: 3.6 × 2.4 meters
Features
- Enhanced Safety: The interlayer holds shards together in case of breakage.
- Strength: Multiple layers increase resistance to impact and stress.
Applications
Laminated glass is widely used in:
- Skylights: Provides protection against debris and enhances safety.
- Glass Floors: Ensures durability under heavy foot traffic.
- Structural Glass Walls: Adds strength while maintaining transparency.
This combination of safety, durability, and versatility makes laminated glass a key material in modern construction.
Johns Hopkins University: Gilman Hall Project
Glass with Ceramic Frit
Glass with ceramic frit combines functionality and aesthetic versatility. It features enamel patterns baked into the glass surface, creating durable and visually appealing designs.
Production Process
- Enamel patterns are applied to the glass using a silkscreen process or other techniques.
- The glass is baked in a furnace, permanently fusing the frit into its surface.
Specifications
- Patterns can include dots, lines, or custom designs.
- Available in various standard colors from the RAL system.
Features
- Enhances privacy by obscuring views.
- Reduces solar heat gain and glare.
- Offers decorative appeal with customizable patterns.
Applications
Ceramic frit glass is commonly used in:
- Curtain Walls: Balances aesthetics and functional solar control.
- Glass Partitions: Provides privacy in office and interior spaces.
- Stair Rails: Adds decorative elements while enhancing safety.
This material is ideal for projects requiring both performance and design flexibility.
Low Iron Glass
Low-iron glass enhances transparency and aesthetics by eliminating the greenish tint commonly found in standard glass. This is achieved by reducing the iron oxide content during production.
Specifications
- Standard Thicknesses: 6, 8, 10, and 12 mm
Features
- Offers exceptional clarity and brilliance.
- Eliminates color distortion, making it ideal for applications requiring true color rendering.
Applications
Low iron glass is widely used in:
- Façades: Provides a seamless and crystal-clear exterior.
- Skylights: Maximizes natural light with minimal color distortion.
- Balustrades: Combines safety and aesthetic appeal.
- Glass Floors: Ensures visibility while maintaining strength and elegance.
- Structural Glass Fins: Adds stability and support without compromising transparency.
This glass is a top choice for projects requiring precision, clarity, and high-end visual appeal.
Body Tinted Glass
Body-tinted glass combines functionality with aesthetic appeal by using specially formulated raw materials to produce colored glass. This type of glass is both visually striking and energy-efficient.
Specifications
- Dimensions: Up to 3.2 × 2.4 meters
- Standard Thicknesses: 6, 8, 10, and 12 mm
Features
- Reduces solar heat gain by absorbing sunlight.
- Helps regulate indoor temperatures and lowers energy consumption.
- Enhances building aesthetics with a range of color options.
Applications
Body tinted glass is often used in combination with clear or low iron glass and is ideal for:
- Facades: Adds vibrant colors to exterior designs.
- Storefronts: Creates attractive and energy-efficient displays.
- Interior Design: Enhances the ambiance of commercial and residential spaces.
- Skylights: Regulates natural light while adding aesthetic value.
This versatile glass is a popular choice for modern architectural projects requiring both performance and visual appeal.
Insulated Glass
Insulated glass units (IGUs) are engineered to provide superior thermal and sound insulation by enclosing a sealed interspace between two glass panes. To enhance thermal performance, the interspace is often filled with air or argon gas.
Specifications
- U-Value (Thermal Transmittance):
- Air-filled IGU (no coating): ~3.0 W/m²*K
- Air-filled IGU (with Low-E coating): 1.6–1.9 W/m²*K
- Argon-filled IGU (with Low-E coating): 1.1–1.5 W/m²*K
- Spacer Materials: Hollow aluminum or stainless steel spacers define the interspace thickness.
Features
- Primary seals (butyl) and secondary seals (silicone) ensure airtight performance.
- Reduces heat transfer and minimizes noise infiltration.
- Improves energy efficiency in buildings.
Applications
Insulated glass is commonly used in:
- Residential Buildings: Enhances comfort and reduces energy costs.
- Hospitals and Hotels: Provides soundproofing for peaceful environments.
- Commercial Offices: Improves energy efficiency and indoor climate control.
- Airports: Ideal for high-demand thermal regulation in cooling towers.
UNLV Hotel College Academic Building Project
Innovations: Low-E Coatings
The thermal transmittance of IGUs can be lowered further using low-emittance (low-E) surface coatings which are microscopically thin, virtually invisible metal or metallic oxide layers. These coatings consist of microscopically thin metallic layers that reflect infrared radiation while allowing visible light to pass through.
- Benefits:
- Reflects radiant heat back into the interior during winter.
- Reduces heat entry during summer.
Innovations: Solar Control Low-E Coatings
Solar control coatings further improve IGU performance in warm climates by reflecting ultraviolet and infrared light. This minimizes heat gain while maintaining excellent natural light transmission.
- Applications:
- Used extensively in regions with high solar exposure.
- Optimizes energy use in commercial and residential buildings.
Conclusion
As evidenced by the production processes listed above, there are different types of architectural glass with varying properties that provide excellent performance and aesthetic appeal for architectural spaces.
Learn more about our architectural glazing systems here, or contact the Novum Structures team today!