DEI’s company philosophy is Integrating Proven Technologies Using Sound Engineering Principles. This philosophy guides all our work with the goal of delivering robust, reliable, and resilient design solutions to our clients. Designs are developed from first principles to ensure that technical performance requirements for each project are met or exceeded. In addition to satisfying technical design requirements of each project, DEI prides itself on building long-term relationships with our clients based on trust, experience, and an understanding of their unique and evolving needs. Our personnel include professional engineers licensed to practice in Ontario (P.Eng) and other North American jurisdictions, LEED® accredited professionals and Certified Energy Managers (CEM®). DEI staff are active members in numerous national and international industry associations including the Ontario Society of Professional Engineers (OSPE), American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), Association of Power Producers of Ontario (APPrO), International District Energy Association (IDEA) and the Canadian Green Building Council (CaGBC).

As a firm, DEI has a deep corporate commitment to sustainability, health and safety, and good governance. These principles are supported through regular employee training and professional development activities, information sessions, volunteerism, donating to non-profits and charitable programs, and promoting environmental protection and long-term sustainable solutions in engineering designs. As the focus on sustainable investment grows worldwide, more clients are seeking innovative approaches to reduce greenhouse gas (GHG) emissions to align with internal and provincial targets. DEI continually works with clients to evaluate and implement projects that improve building performance, reduce emissions, increase operational savings, and enhance human health benefits.


Year Established




Projects Completed



Meet Our Team

Adrian Spaziani

Project Manager

Aline McMullen

Project Manager

Arnar Valmundsson

Project Manager

Brett Friesen

Project EIT

Curtis Singh

Senior Technologist

David Sebastian

Project Manager

George Jones

Senior Project Manager

Graham Loney

Project Engineer

James Gillis

Senior Project Manager

Jamie Minaret

Project EIT

Kayla DiBattista

Manager, Finance and Operations

Martino Beretta

Senior Project Manager

Matthew Doherty

Manager, IT Operations

Michael Johns

Senior Project Manager

Mira Toutounji

Engineering Graduate

Paul Vogt

Senior Project Manager

Preet Noor

Manager, Marketing and Business Development

Sharmeen Qamar

Administrative Assistant

William Zammit

Supervisor, IT and Quality Assurance


Association of Consulting Engineering Companies Logo
The Association of Energy Engineers Logo
The American Society of Heating, Refrigerating and Air-Conditioning Engineers Logo
American Society of Mechanical Engineers Logo
Institute of Electrical and Electronics Engineers Logo
Professional Engineers Ontario Logo

Community Involvement

Environmental Conservation

Doherty Engineering strongly believes in ecofriendly business practices. Many of which include promoting environmental protection in engineering designs, renewable energy options and ideas to reduce carbon footprint.


Paul Doherty conducts mentoring programs for Kids in Ice Hockey. Mentoring and teaching the importance of mental and physical balance, mental and physical agility, coordination, and team spirit. They learn how to strategize and operate as a team, each contributing their own strengths.

Charitable Giving

Doherty Engineering gives back to the community in numerous ways including, donations to employee and client causes, sponsorships of charity golf tournaments, donations to support undergraduate student, and many more.