Our Principals

Aron McCallum, P. Eng. – Principal

Aron McCallum has over 15 years of experience in structural design, specializing in institutional projects.  He is a trusted project manager and team leader, overseeing the design and construction of many fire / EMS stations, municipal works, libraries, and elementary, secondary and post-secondary education facilities. He has experience in both new construction as well as addition / renovation work.  Aron is also an experienced project leader for residential, commercial and recreational developments. Recent notable work includes Alton Secondary School, Library and Community Centre, Guelph South End Services Fire / EMS Station, Mississauga Fire & Peel Emergency Services Station and Durham College Culinary Arts Centre. In addition, Aron is the Structural Consultant to the Heavy Urban Search and Rescue (HUSAR) Large Disaster Team, providing emergency structural engineering consultation to specially trained rescue teams during national emergencies.

Mohsen Mansouri, P. Eng., LEED AP – Principal

Mohsen Mansouri is a professional engineer with more than 25 years of experience in the structural review, restoration and design of a wide variety of structures, including commercial, residential and institutional facilities, parking garages, bridges, and other concrete projects. Mohsen offers his strong leadership and project management skills, and his extensive knowledge of building science principles, systems, and components to all clients. He also provides clients with service and cost-effective, durable design solutions.

Mohsen is responsible for leading the Building Science division at Stephenson Engineering.  In addition to concrete and building envelope restoration services, Mohsen and his team have significant experience in asset management, feasibility studies, small projects, sustainability consultation, and design services.

Saundra Cullen, P.Eng., LEED® AP – Principal

Saundra Cullen has been an integral member of the Stephenson Engineering team for over 35 years. She possesses a hands-on management style and enjoys collaborating with clients and colleagues to design practical and innovative solutions to structural challenges. Saundra specializes in the design of health care and high-rise residential projects. Some of  her recent notable work includes: The Four Seasons Hotel & Residence in Toronto, Waypoint Mental Health Centre in Penetanguishene, the new Halton Regional Hospital in Oakville, Picasso Condominium in Toronto and the 90 Harbour / One York mixed-use development in Toronto. Saundra served two terms on the Council of Professional Engineers of Ontario and is a past member of the PEO Disciplinary and Complaints Committee.

Zoran Tanasijevic, P. Eng. – Principal

Zoran Tanasijevic has over 20 years of experience in structural engineering, designing and managing projects in all major sectors of development. He has a passion for structural design that is evident in his attention to detail, creative and practical design concepts, and attentive client service. Zoran has worked on a wide variety of projects including data centres, airports, commercial, residential, and institutional buildings in Canada, the United Kingdom, the Middle East, Russia, North Africa and the United States. With experience in all sectors of structural design, examples of his work include Ryerson University Student Campus Centre, Bank of Montreal Computer Centre, Casino Rama, and Southcore Financial Centre.

Robert Sqapi, P. Eng.,Ph.D – Principal

Robert Sqapi has 26 years of structural engineering experience in the structural design of buildings, project management, and business development both in Canada and internationally. Robert has proven management skills and expert experience in the structural design and contract administration of a diverse range of building types of varying complexity and size requiring innovative and unique solutions to suit the particular challenges of each project in the areas of commercial, office, residential, healthcare, industrial, institutional, retail, high security, parking, sacred spaces, and special purpose structures.