Visual appeal
Windscreens made from glass can offer a modern, sleek look and provide unobstructed views. In cases when the system is installed on a rooftop, these glass walls can provide a 360-degree, panoramic view of an entire landscape. Depending on the manufacturer, windscreens can be designed with hidden fasteners to bring additional sleekness to the building. Common types of installation involve vertical posts with panels spanning between or a base metal U-channel or shoe with glass extending upward (no posts). Typically, glass is tempered and laminated. When acting as a guard, the windscreen must be 1067 mm (42 in.) from the walking surface, though, as previously mentioned, it is commonly detailed and provided at 2 m.
Noise reduction
The use of tall, thick glass—13 to 19-mm (1/2 to 3/4-in.) laminated variety is common—provides a much higher sound transmission rating than conventional railing systems, meaning less noise is able to penetrate the surrounding area. Due to the solid (versus picket or cable) infill panels, the sound is reflected off the glass, reducing noise from adjacent roadways. This is especially beneficial for outdoor spaces alongside busy roads and noisy urban areas.
Design flexibility
Glass windscreens can be custom designed to meet the performance and safety requirements of any project. These requirements will be dictated by building codes and possibly by the design team or architect responsible for creating the performance specification. For instance, some windscreen products are designed to resist environmental loads including those from seismic events and wind loads, with the latter normally causing the highest demands.
Most commercial windscreen systems are capable of resisting wind loads of around 479 Pa (10 psf), while others are designed for up to eight times that amount, with a service-level wind load capacity of more than 3830 Pa (80 psf). This pressure typically corresponds to ultimate three-second gust wind speeds of 185 to 274 km/h (115 to 170 mph). An increased wind load allows for installation at much higher elevations. The wind pressure should be determined by a qualified professional engineer, as it is dependent on many factors, such as building geometry and height, geographic location of a project, type of building, and location of the railing on a building.
Low maintenance
Glass windscreens are designed to resist the elements. Concept designs or systems are typically detailed by the project architect or a system from a particular vendor is specified. Quality finishes, such as anodized or powder coated, can provide an aesthetic color and enhance the durability of the windscreen surface, making them more resistant to corrosion. Exposed edges of the glass are typically polished smooth.
Improved safety
Not only do windscreens serve as protective barriers against strong winds, but also guard railings providing fall protection. Additionally, windscreen systems should be designed with ease of assembly in mind, enhancing safety for installers as well.
Specification considerations
While glass windscreens may be one of the last products to be installed, their specification should
be considered early in the design process—ideally at concept—as the structure must be designed to support the system. There are four critical aspects to consider when specifying a glass railing windscreen system.
Materials and components
An understanding of typical glass windscreen material properties will help when evaluating conditions and designing new systems. Windscreen systems are designed and constructed using laminated glass infill. Polyvinyl butyral (PVB) or a more advanced and high-performing architectural safety glass interlayer is commonly used with 1.5 to 2.5 mm (59 to 98 mils) thickness, both tempered and laminated, as well as aluminum, steel, or stainless steel framing. Using these types of structural components allows for corrosion resistance. These components are lightweight and offer a selection of protective finishes.
Structural compliance
In addition to applicable local codes, architects, engineers, and contractors must comply with the structural and load requirements of the IBC to provide a quality, tested, and proven safe product. In most areas, glass railing windscreens must be able to withstand at least 91 kg (200 lb) of concentrated force at all times, including the force of high winds, especially atop multistory buildings. For instance, some glass windscreens systems are capable of resisting wind speeds up to 249 km/h (155 mph). Systems can be engineered and tested to meet the requirements of Miami Dade County and other wind borne debris regions. Windscreens are often considered guards, and must withstand 23 kg (50 lb) per linear foot of load.
