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Recent developments in point supported structural glass systems have afforded a wealth of options when it comes to designing feature areas of your building. However, as designs become more complex and buildings become increasingly more transparent, the technology behind the systems becomes more complex as well. The increasingly complex nature of point supported glazing systems makes it all the more important to understand if your system is fully tested to meet all of the specific criteria for your project.


Point supported glazing systems are made up of exterior face glass, stainless steel fittings, and a backup member/structure all working together to create a uniform assembly. Throughout the entire process, W&W Glass makes certain each component is rigorously tested and meets very high testing requirements. Heat Soak Testing helps to limit the statistical probability that glass with nickel impurities (also known as nickel sulphide inclusions) which can cause spontaneous breakage when the glass is in service, are broken in a test chamber instead of on the jobsite. Strain Gauge tests make sure that the countersunk holes drilled into the glass are capable of holding both vertical dead load, horizontal wind loads and even accommodating seismic movement. The Uniform Load test stresses the glass beyond its breaking point and ensures that the laminate layer and system will support the weight of the broken glass so that it can be safely braced to be changed. Finite Element Analysis shows how the glass will react to loading from anticipated stress conditions. The glass system then goes for various other tests for wind conditions, seismic resistance, water penetration performance and so on. A system manufacturer should have all of this information available for review from previous projects to ensure the system meets all project criteria.


There are also hardware and structural back-up system tests in place to ensure the whole system is structurally sound. “Spiders”, “patches”, or “905” type fitting systems are the most common in the industry and adhere to rigorous specifications based on the requirements of the building design. Various supporting structures are also tested and versatile enough to meet the desired aesthetics. Structural glass fins undergo buckling analysis to make sure they can support the proper load, especially for taller façades. Steel and tension supported structures allow for very high-tech innovative designs.

W&W Glass and Pilkington ensure that each component included in the Pilkington Planar point supported glazing system design is fully tested and fail-safe against progressive collapse (which is extremely important for glass fin walls). Pilkington never supplies hardware or glass produced by another company to ensure sole-source responsibility which allows them to offer a 12-year furnish and install warranty on the project to the Owner. Every part of the system is meant to work together to create the safest and most structurally sound design possible. With W&W Glass, you know you are getting the true Pilkington Planar system, and not separate glass and hardware components coupled with some engineering that may not work together from a firm that does not actually have a hand in manufacturing anything. Be sure to check specifications to ensure the quality levels and system testing required for your point supported glass system are being reached. Otherwise, buyer beware.


W&W Glass LLC is a family owned business with a 70-year history in the metal and glass industry, one of the largest metal and glass companies in the New York metropolitan area and the largest supplier of structural glass systems in the country. We have over two decades of experience in the design and installation of various building enclosure systems, including stick-built curtain walls, pre-glazed unitized curtain walls, Pilkington Planar structural glass facades and custom metal and glass enclosure systems. We install all of our work with our own dedicated union labor force. W&W is consistently the largest employer of glaziers in the NY metropolitan area.

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