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O’Donnell & Naccarato – Philadelphia Office

Established in 1981, O’Donnell & Naccarato is a structural engineering firm in Philadelphia. The Philadelphia headquarters is the firm’s largest office and acts as a hub for national structural design and restoration projects. Below is the contact and project information of the Philadelphia office of O’Donnell & Naccarato.

701 Market St, #6000
Philadelphia, PA 19106
Phone: (215) 925-3788
Email: info@o-n.com

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Our Structural Engineering Projects in Philadelphia

We take great pride in our work at O’Donnell & Naccarato, providing innovative technology, design, and excellent structural engineering services to our clients and communities, both national and in Philadelphia. Below are just a few of the projects our structural engineering firm in Philadelphia has worked on.

Loews Philadelphia
Philadelphia, PA

Loews Philadelphia Hotel, locally known as the PSFS Building, is a skyscraper in Center City, Philadelphia, Pennsylvania. A National Historic Landmark, the building was the first International-style skyscraper constructed in the United States. The hotel sits in a prime Center City location, surrounded by the Pennsylvania Convention Center, Chinatown, the Avenue of the Arts, and many more historic and cultural landmarks.

O’Donnell & Naccarato’s structural engineering firm in Philadelphia performed a façade assessment of the skyscraper that included the steel-framed antenna extending above the roof in 2017. Our team of certified rope access engineers were able to investigate the skyscraper up-close while not disturbing the daily operations of the hotel. Following our investigation, we were contracted to address deteriorating limestone, brick masonry, corroded steel framing, sealants, and to provide flashing improvements. You can read more about our work with Loews Philadelphia here.

Structural Engineer | Facade Restoration | Loews Philadelphia | Philadelphia, PA | Side view of PSFS sign | O’Donnell & Naccarato

Parkade On 8th
Philadelphia, PA

O’Donnell & Naccarato provided structural engineering design and restoration services to repair, modernize, and beautify the 6-story, 1,200-space parking garage, and 30,000 SF of ground-level retail space. Improvements included repairs throughout the garage, and more noticeably, significant aesthetic renovations to dramatically alter the building’s exterior appearance. On the North elevation, screening with colored glass louvers that shimmer and reflect light add visual interest while helping to obscure the structure’s decks. Learn more about the project here.

O’Donnell & Naccarato in the News

Matthew Mowrer, restoration engineer and senior project manager at O’Donnell & Naccarato, a structural engineering firm in Philadelphia, won the International Concrete Repair Institute (ICRI) 40 Under 40 Award in 2020.

O’Donnell & Naccarato is proud to announce that Matthew Mowrer, PE was amongst the announced winners. Matt was on ICRI’s Board of Directors for 4 years and was the past president of the Delaware Valley Chapter in 2016. He is also a voting member of two technical committees: Committee 320 (Concrete Repair Materials and Methods) and Committee 510 (Corrosion).

Read the full press release here.

Our Specialties & Mission

O’Donnell & Naccarato is a structural engineering firm that specializes in facade restoration, parking garage restoration, and structural design. Our Philadelphia, PA office offers innovative alternatives and efficient designs that keep costs in line and allow for ease of construction. We strive to provide the most in-depth analysis so that each building will support the design and system elements critical to its unique architectural expression and purpose.