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Clean and Transparent

Ensuring the Washington Beltway has an adequate supply of clean and usable water, not to mention taking sewage away in a safe manner, takes a lot of innovation and manpower. Alexandria Renew (AlexRenew) supervises all the sanitation issues for Alexandria, Virginia and the surrounding areas. To have a centrally-located headquarters for the company required some ingenuity without sacrificing efficiency or style. The headquarters is a major development initiated by Alexandria Renew Enterprises, formerly known as the Alexandria Sanitation Authority. This project is a 6-story, 60,000 square foot office building that serves as the new hub for the sanitation authority. The project involved construction of an innovative and new Nutrient Management Facility and related buildings on the west side of the existing Alexandria Renew campus. The new building houses the organization’s employees and allows the company to better manage the biological treatment process that removes nitrogen from wastewater. Large concrete holding tanks, a pump station, electrical facilities and an odor control system works in tandem to produce water that meets all environmental standards and helps in the effort to clean and renew the Chesapeake Bay. Just like the work the company does, the building is a combination of science and innovation.


Designed by Rust-Orling Architecture, this sustainably-designed building offers office, training, and meeting space for AlexRenew. It also serves as a community resource to educate the public about the environment, sustainability, and clean water, offering educational displays and tours to local school and community groups. Adjacent to the Center is Alexandria’s advanced water resource recovery facility, a public utility that makes dirty water clean and usable again.

All jokes aside, sanitation is a dirty business and a safe environment is a primary goal. The team from Rust-Orling selected structural glass specialists W&W Glass to assist in the design and engineering of the exterior lobby enclosure. With their detail and product assistance, in combination with installers from Innovo Construction, Inc. , they came up with solutions that were efficient while provide a striking appearance and stylish entrance that allows maximum natural light and energy efficiency.


For the massive, multi-story lobby and atrium spaces, W&W Glass supplied a Pilkington Planar™ system with face glass comprised of Pilkington Optiwhite™ low-iron, low-e silk-screened insulating glass units with HP 73/42 low-e on the #2 surface. The full surface frit silk-screen on the insulating glass has a 20 percent coverage white dot pattern on the #3 surface to help with shading and glare control. The vertical walls are just the beginning as they support an insulated glass roof return at the top made with low-iron, low-e coated SentryGlas® interlayer laminated glass and utilize the same  HP 73/42 low-e on the #2 surface and dot silk-screen pattern on the #3 surface. The vertical glass fins supporting the facades and roof are made from 3/4″ Pilkington Optiwhite™ low-iron monolithic tempered glass.

Upon entering, you notice an upscale interior all glass vestibule constructed with a low-iron SentryGlas® interlayer laminated glass. The main facade transitions at the top to a point-supported laminated glass railing made from a similar laminated glass composition. The railing is mounted to a stainless steel blade structure. All components are mounted with countersunk Pilkington Planar™ 905 series fittings except for the unsiliconed railing glass which was capped. 


There were some very challenging features that required a high degree of engineering on the point-supported glass areas of this project. The first was the glass fin-supported skylight roof return where the vertical walls return back 2 feet to an area just below an aluminum curtain wall system. There needed to be an additional L-shaped glass fin section connected to the vertical fin in front and turning up behind the aluminum curtain wall to meet the slab in back. Engineers at W&W/Pilkington had to devise a solution to this custom solution, as they do with many projects, since conditions are always changing… even though the main system principals remain the same. The second was the multi-story glass facade with fins clear spanning almost 23 feet to the bottom of third floor where the face glass continues up above for the next 39 feet, but is interrupted at the next three floors by concrete slabs. Each floor has vertical glass fins in fin shoes supporting the face glass thereby loading the system to the base at each level. Live load deflection was a main force that needed to be controlled very tightly, less than 1/4″ at each floor, so that the face glass could move properly with each of the floors.


The other area that had to be addressed, as related to the multi-story structural glass wall, was fire-safing the edges of the concrete slabs behind the point-supported glass system. In the event of a fire, the point-supported glass system would not withstand the heat, so it would be assumed to burn away. However, the floor slab conditions must remain fire-rated as prescribed per code for protection of fire spread to other floors. There were special fire-rated slab assemblies that were supplied by Innovo Construction to handle these conditions extending in front of the slab (with an additional 4 inches above and below it). There was a cold smoke seal applied with a continuous backer rod on an angle and continuous fire sealant with bond breaker tape between the backside of the glass and the fire rated assembly near the top of each assembly. These details are always tricky and W&W Glass always recommends that they should be reviewed by a fire code consultant for an engineering judgement and an authority having jurisdiction for approval. They arise more often than you think and engaging the experience of a quality structural glass system designer and fabricator early on in the design process is very helpful for ideas.


The structural glass enclosure is not the only hi-tech feature of the building. The main building facade uses a high-performance curtain wall and glazing system, thereby reducing energy consumption for lighting by more than 30 percent. Other unique features include a demand-control ventilation system with magnetic-bearing centrifugal chiller and a heat-recovery chiller-heater used to preheat domestic hot water. The building also includes solar panels, a living wall, and a reclaimed water system, which is located between AlexRenew’s treatment tanks and planned residential and commercial areas. An educational lobby within the building features exhibits promoting water stewardship and awareness of water resource recovery. Reclaimed water is used to irrigate the surrounding landscape. In addition, the building provides meeting space for local nonprofits, and the ultimate partnered design connects to a neighborhood bike and pedestrian path. The most innovative aspect of the design is that all major treatment facilities, as well as structured parking, is hidden under a major recreation and park area that is set to transform the surrounding community. AlexRenew is certainly a welcomed addition to a growing DC area.

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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