Crystal Window & Door Systems played a pivotal role in the glass transformation of 650 First Avenue, a 131-year-old historic building in Manhattan. The project involved a vertical expansion, adding four new floors atop the original seven-story brick structure, fully encased in Crystal’s Series W50i Window Wall System. Over 11,000 square feet of glass façade now defines the rooftop addition, featuring curved glass corners for a striking architectural crown.
The Series W50i system, a 5-inch deep aluminum window wall with a polyamide thermal break, combines floor-to-ceiling views with high performance. Panels up to 10 feet tall were dry-glazed and included operable in-swing casements, terrace doors, and spandrel sections.
U-values ranged from 0.215 to 0.419, meeting New York City energy codes, while sound attenuation ratings of STC 32–43 ensure urban noise reduction. The unitized system allowed fast interior installation and incorporated durable two-tone AAMA 2604 powder-coat finishes.
For the historic base building, Crystal supplied 238 high-performance Series 9200 aluminum windows in in-swing casement and fixed picture styles. Bird-friendly glazing and dual-pane low-E glass with argon enhanced energy efficiency and safety. The combination of W50i window walls and Series 9200 replacement windows demonstrates the versatility of modern architectural glass systems in both historic preservation and contemporary urban design. 
Source: Crystal with additional information added by Glass Balkan
