Commercial Wood Window Replacement for Historic Office Building

Built between 1895 and 1897, the Witherspoon Building is an 11-story historic masterpiece in downtown Philadelphia, Pennsylvania. Designed by architect Joseph M. Huston, it is faced with brick and granite and features Corinthian-style columns, statues, medallions and more. The building is named after John Witherspoon, the sixth president of Princeton University and it was added to the National Register of Historic Places in 1978.

The original 120+ year-old windows were becoming worn out and dysfunctional. Working with Domus Construction and JKRP Architects, Pella was entrusted to select optimal windows that would get the job done right. The Pella representative recommended Pella® Reserve™ wood windows for the unparalleled historical detailing, high customizability and excellent energy efficiency they provide.

Resembling replacement windows to the historic building's originals was of highest importance. That’s one of the primary reasons for selecting Pella Reserve windows, which have been reviewed and approved on a case-by-case basis by the National Park Service for use on projects with historic tax credits. To maintain the building’s historical accuracy, the team paid close attention to preserve the details of each window. They were able to do so by copying the custom extruded brickmould on the second floor.

Selecting putty profiles for the windows helped recreate the historically accurate angles. The Pella Reserve windows they selected offer the industry’s deepest sash dimension, providing depth and a realistic shadow. Butt joinery and through-stile construction are also essential to the tradition of window making. These techniques create authentic proportions and emulate historic window design. As a finishing touch, the team selected authentic spoon-lock window hardware inspired by period furniture. The hardware delivers authentic, traditional style that honors the history of the building while updating performance and functionality of the windows.

When selecting new windows for the building, the ability to customize was key to maintaining historical authenticity. Pella Reserve products feature cutting-edge innovations without compromising on the integrity of this building’s unique design. Tailor-made for this specific project, these windows were built to replicate the exact size and traditional profile of the originals. As our most customizable product line, Pella Reserve windows can be built extra tall and extra wide, with custom finishes, wood types and glass options available.

Wood windows are also high quality and very durable. Low-maintenance aluminum cladding on the exterior of these windows protects them from the elements, resisting rot and corrosion. In selecting wood, the team was confident they were choosing quality windows that will last for years and years to come.

While historical accuracy was the primary goal of new windows, energy efficiency was definitely an added benefit. The 120+ year old original windows were drafty and inefficient. In comparison, the new windows provide a night-and-day performance difference. Pella partnered with the contractor and architect to select window glass optimized for this region. In a part of the country with varying temperature, the Low-E glass coating reflects heat back into the building in the winter and away from the building in the summer. Plus, with professional help, the property owners rest assured knowing the windows were properly installed to block air infiltration.

If you’re interested in learning more about partnering with Pella on your next commercial project, request a free project quote.