Joseph B. Callaghan, Inc. is a structural engineering firm that is driven by the challenges of the built world. We are committed to providing innovative solutions to Clients at every stage of the structure’s life, from the design of new construction to rehabilitating existing facilities. Our staff is involved in all phases. What sets us apart are our established relationships, reliability, and response with our Clients. We are a certified Small Business Enterprise (SBE) in Pennsylvania and New Jersey.


  • 2017 Zweig Group Fast Growth Award
  • 2017 ICRI Award of Merit in the Water Structures category for Carnegie Lake Dam for Princeton University
  • 2017 Preservation Alliance of Greater Philadelphia Grand Jury Award for Renovation of Park Towne Place Museum District Residences
  • 2017 Preservation Alliance of Greater Philadelphia Grand Jury Award for Renovation of Mansion Building at the Academy of Notre Dame de Namur
  • 2017 DVASE Excellence in Engineering Award for Carnegie Lake Dam for Princeton University


  • American Concrete Institute (ACI)
  • American Institute of Steel Construction (AISC)
  • American Society of Civil Engineers (ASCE)
  • Association for Preservation Technology International – Delaware Valley (APTI)
  • Community Design Collaborative (CDC)
  • Delaware Valley of Structural Engineers (DVASE)
  • Healthcare Facilities Management Association of New Jersey (HFMA)
  • Greater Philadelphia Condominium Managers Associations (GPCMA)
  • International Code Council (ICC)
  • International Concrete Repair Institute (ICRI)
  • International Facilities Management Association – New Jersey (IFMA)
  • New Jersey Association of Physical Plant Administrators (NJAPPA)
  • National Council of Structural Engineers Association (NCSEA)

Meet The Team

Allen Roth, P.E.


Mr. Roth joined Joseph B. Callaghan, Inc. as a Project Engineer in 1984, and advanced to Vice President in 1992. In 2015, Mr. Roth assumed the responsibilities of President. His experience includes structural design and analysis of reinforced concrete, structural steel, masonry and light gauge steel of both new and existing structures. However, his expertise is in the field of building envelope, water abatement and building technology. He is responsible for supervising the engineering staff and final review of the construction documents. He has been the Project Manager for design, documentation and construction administration for the Structural Condition Evaluation and Repair and Building Façade projects.

Joseph Philips, P.E.

Director of Engineering

Mr. Philips joined the firm as a Project Engineer in 1993. His professional experience ranges from the design of new structures to the repair and restoration of existing structures. He has been the Project Manager for design, documentation and construction administration on rehabilitation projects, structural and exterior façade investigations, parking garage investigations and forensic studies. Most recently, he was promoted to Director of Engineering in 2011.

Erik Villari, P.E.

Project Manager

Mr. Villari, while attending Rowan University, was employed by the Delaware River Bridge Authority preparing finite element analysis on the Betsy Ross Bridge. Upon completing the Masters Program at Penn State he was employed by a consulting engineering firm as a bridge engineer. Mr. Villari joined our firm in 2006. Since that time he has been performing structural engineering design and assessment services on an array of projects.

Jessica Clifford, P.E.

Project Manager

Ms. Clifford began her career performing space planning and providing analysis for The City of Philadelphia Capital Program Office during the Cooperative Education Program at Drexel University. Upon graduating in 2006, she joined our firm as a Project Engineer and after earning her Professional Licensure, has since been promoted to Project Manager. Her expertise is in the field of building envelopes, water abatement, building technology and historical preservation.

Diane Goschler, E.I.T.

Project Engineer

Ms. Goschler rejoined our firm in 2011 and has been performing Facade Compliance Inspections for the City of Philadelphia, construction administration services and prepared condition surveys, due diligence reports, project specifications and maintenance programs.  She also provides in-house and on-site construction support.  Ms. Goschler has experience in engineering assessments; failure analysis and historical preservation design, and is experienced in waterproofing, concrete and masonry consulting, including garage, balcony and plaza deck repair, masonry facade and historic restorations.

Ben Bruening, PE

Project Engineer

Mr. Bruening joined us in 2015 from a consulting architecture and engineering firm where he was the design engineer for new data center and parking garage projects as well as a number of other new design and renovation projects. He attended Temple University with a Bachelor of Science in Civil Engineering. He lives in the Fairmount section of Philadelphia with his wife Jenna and enjoys hiking and backpacking around the region as well as abroad.

Colleen Boulden, E.I.T.

Project Engineer

Ms. Boulden began her career interning with our firm before entering her senior year at the University of Delaware. Upon graduating in 2009, she joined our firm as a Project Engineer. She has experience in façade and building envelope assessment and repair, waterproofing, and concrete repair including balcony and garage repair.

Michael Salera, E.I.T.

Project Engineer

Mr. Salera, upon graduation from Villanova University, joined our firm in 2012.  He has gained extensive experience in the structural analysis and design plus façade assessments.  He has analyzed many building materials including, reinforced concrete, structural steel, limestone, brick masonry, terra cotta and cold form steel.  He has assisted in facade inspections and performing construction administration services on projects.

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