Westfield Washington Public Library and Westfield Washington Township Trustee Office

The building is a 2-story braced frame structure with multiple roof elevations that aid in concealing rooftop mechanical units. While the second level consists of structural steel tube columns and composite wide-flange steel framing, a combination of non-composite wide-flange beams and open-web steel joists frames the roof.     

The primary challenge for the structural engineering team involved achieving the look and feel envisioned by the owner and architect at an affordable price. This required innovative thinking to use readily available materials and standard fabrication techniques to achieve a custom look. For example, large open spaces with an abundant amount of natural light were strongly desired on the building’s eastside which included varying roof elevations. Our structural engineers framed the building in a way that focused on minimizing member depths to create large open spaces that were not impeded by visible structure while also maintaining the structure’s overall lateral stability. By using a deeper steel deck, our structural engineers increased the spacing between roof joists to align directly with the exterior perimeter columns. This minimized the framing congestion and helped conceal the framing from the exterior while not significantly increasing the overall cost.

To further achieve the desired look, the structural team coordinated with the architects to indicate specific member shapes for the joists. To provide localized lateral stability to the small pop-up roof, deep structural steel members were used in combination with elevated, conventional braced frames. This allowed smaller areas of the roof to function as an extension of the global lateral system, allowing more unobstructed space for the exterior glazing. Additionally, the structural team collaborated with the architects to design a large, monumental stair feature that also included tiered seating levels. The stair creates a “wow” factor providing access to the second level and seating where the public can read or have small gatherings.