Greg Williamson

Greg Williamson brings over 40 years of plumbing industry experience to ITDG's in-house mechanical operation. Before leading ITDG's plumbing division, Greg served as General Manager of Catalina Mechanical Contracting for over 30 years, where he supervised more than 150 employees and built a reputation as one of the most respected plumbing leaders in Southern Arizona.

His responsibilities span the full scope of the mechanical department — from estimating and design through installation and final inspection. Greg doesn't just execute plans; he optimizes them, applying four decades of field knowledge to engineer plumbing systems that perform better and cost less.

He has performed residential, commercial, and industrial plumbing systems for every major builder in Southern Arizona, as well as national and out-of-town clients. That breadth of experience means there isn't a plumbing challenge he hasn't seen and solved — from complex industrial piping to medical gas systems to large-scale multifamily installations.

As ITDG's Plumbing Division Manager, Greg is a key reason the vertically integrated model works. When plumbing is self-performed by someone with his depth of expertise, coordination with the electrical and HVAC divisions happens seamlessly — eliminating the scheduling conflicts and rework that plague subcontracted plumbing operations.

His leadership ensures that one of the most critical MEP trades is always executed to the highest standard, on schedule, and under one roof.