Introduction of glass curtain wall technology

Glass curtain walls represent a contemporary and aesthetically innovative method of architectural wall decoration. They have become a prominent feature of the modernist era of high-rise buildings and are indicative of the future direction of modern skyscraper development. Let's delve into the design standards and considerations for glass curtain walls to gain a comprehensive understanding.
 

Glass Curtain Wall Overview:

A glass curtain wall is a modern architectural wall system formed through the combination of a structural framework and glass. It not only serves as the primary structure supporting the building's outer enclosure but also contributes to its aesthetics and decor. Glass curtain walls are typically constructed using a combination of mirror glass and regular glass, with the interspace filled with dry air or inert gas within insulated glass units.
 

Glass Curtain Wall Design Standards:

1. Steel Materials:

   • The surface of steel materials must undergo galvanization treatment or be coated with inorganic zinc-rich paint.

2. Aluminum Alloys:

   • Surface treatments for aluminum alloys include anodizing, electrophoretic painting, powder coating, and fluorocarbon coatings.

3. Sealing Methods:

   • For hidden-frame and semi-hidden-frame glass curtain walls, neutral-cure structural silicone sealants must be used for glass and aluminum bonding. Coated glass in full-glass curtain walls and point-supported curtain walls should avoid acidic silicone structural sealants.

4. Thermal Break Materials for Aluminum Profiles:

   • For thermal break aluminum profiles, the insulating material can be polyamide with glass fiber pouring or polyurethane.

5. Stainless Steel Usage:

   • Austenitic stainless steel, with a nickel content not less than 8%, is recommended for stainless steel components in glass curtain walls.

6. Insulating Glass:

   • For insulating glass in glass curtain walls, with a gas layer thickness greater than or equal to 9mm, a double-seal approach is recommended: primary seal using butyl hot melt sealant and secondary seal using silicone sealant.

7. Laminated Glass:

   • The interlayer for laminated glass in glass curtain walls should preferably be made of polyvinyl butyral (PVB).

8. Rubber Products:

   • Rubber products in curtain walls should be made from EPDM rubber, chloroprene rubber, and silicone rubber.

9. Operable Panels:

   • The angle of operable panels should not exceed 30 degrees, the opening distance should not exceed 300mm, and for heights exceeding 40 meters, cleaning devices should be installed.

10. Air Tightness:

    • When heating, ventilation, or air conditioning is required, the air tightness of the glass curtain wall should not be less than level 3.

11. Glass Selection:

    • Reflective glass with a reflectance ratio not exceeding 0.3 is recommended for glass curtain walls. The light reduction coefficient for glass curtain walls with daylighting requirements should not be less than 0.2.

In conclusion, adhering to these design standards ensures the quality, safety, and efficiency of glass curtain walls. These guidelines, formulated by relevant national authorities, contribute to the systematic and regulated development of the glass curtain wall industry, ensuring that these architectural elements continue to be a hallmark of modern design and construction.