Calhoun W. Cox, Jr., Founder

Cal Cox grew up in Seneca, South Carolina and received his Bachelor of Science from Clemson University in 1964.

He served in the Army Corps of Engineers/Special Forces for seven years and is a veteran of the Vietnam War.

Cal worked in the construction industry for 36 years and founded Calcon Constructors in 1981 in Denver, Colorado.

Throughout the years, Cal served as the President of the Associated General Contractors of Colorado, as well as on numerous boards and committees. 

James P. Bosshart, Co-Founder and Chairman

Jim graduated with distinction from Iowa State University with a Bachelor of Science in Construction Engineering.

Jim co-founded Calcon Constructors in 1981 and currently serves as Chairman. He is involved in all business aspects, including marketing, estimating, project management and office management.

Jim is very involved in the industry; he has served on many committees, including a position as Executive Committee Board of Directors for the Associated General Contractors of Colorado.

Joseph S. Gallion, Jr., CEO

Joe, who received his education from Colorado State University, has been with Calcon since 1982, and currently serves as the company’s CEO.

Joe is responsible for all business aspects, including: marketing, estimating, project management and field management.

He remains very active in the construction industry, and has held positions as the Chairman of Colorado Neurological Institute, Chairman of the Board for Southwest Family YMCA and as the past President of the Construction Industry Training Council.

Presently, Joe sits on the board of AGC Colorado and is a member of the National Western Stock Show.

When not in the office, Joe enjoys golfing, skiing, cycling and traveling.

Brian Mortimore, President

Brian has been with Calcon since 1999 and is currently a President of the company. He is a proud CSU alumnus and graduated with a Bachelor’s degree in Construction Management.

With over 20 years of experience in Project Management, Brian is a vital asset to Calcon’s customers and vendors.

Brian has completed many notable projects for Calcon in the retail, technical, healthcare and mixed-use categories.

He is LEED AP certified and a Certified Healthcare Constructor.

In his free time, Brian enjoys golf, the outdoors and spending family time with his wife and twin girls.

Jim Sexton, CFO and Vice President

Jim Sexton has dedicated his career to construction-related accounting and finance since relocating to Colorado in 1999. Joining the Calcon Team in 2013, he brings extensive expertise as a Certified Public Accountant (CPA) and Certified Construction Industry Financial Professional (CCIFP). Jim earned his Bachelor of Science in Accounting from Northern Illinois University.

Currently serving as CFO, Vice President, and Stockholder, he oversees all facets of accounting, financial reporting, information technology (IT), and human resources (HR).

Outside the office, Jim finds solace in golfing and exploring the great outdoors of Colorado.

Jeff Johnson, Vice President

Jeff joined Calcon in 2007 and is currently a Vice President of the company.

He has a Bachelor’s degree in Construction Management from CSU and brings 19 years of Project Management experience to the table.

Jeff has completed many of Calcon’s most notable builds in the healthcare industry, including: specialty medical facilities, medical office buildings and hospitals.

Jeff is a LEED Green Associate, Certified Healthcare Constructor and a member of CAHED and ASHE.

When not at work, Jeff enjoys time with his wife and two girls.

Jim Van Zant, Vice President

Jim joined the Calcon family in 1986 and has been in involved in many of our most notable builds.

Jim graduated from Colorado State University with a Bachelor of Science degree in Industrial Construction Management.

He is currently a Vice President and also serves as a Senior Project Manager. He handles pre-construction, estimating and project management for Calcon’s projects, seeing them through construction, closeout and warranty

Jim presently serves as Treasurer and on the Board of Directors for the Construction Industry Training Council (CITC), which offers apprenticeship programs for the construction trades.  He is also a member of the American Society for Healthcare Engineering and has received their Healthcare Contractor’s Certificate.  He has served as an instructor for a project management class offered by Associated General Contractors.

When not in the office, Jim enjoys the outdoors, his family and his ever growing motorcycle collection.

What we do



At Calcon Constructors, we hold onto a deep conviction that great relationships— whether with our clients, employees, or our partners— are the keys to our success.

We leave nothing to chance and ensure that each client and project receives our signature personalized approach.


Over time, we’ve developed a process that ensures quality, transparency, collaboration, and creativity.

Initial client discussion

We start with an initial project discussion to discover our client’s goals, vision, timeline, and all the other nitty-gritty details.

Assemble a dream team

After our first meeting, we will assemble a team of handpicked professionals that will take on your construction project.

We cover every aspect of the construction process, thanks to an experienced team consisting of a principal, a project manager/estimator, a project coordinator and a superintendent. These members will work with you to establish a truly customized experience.

Crunching the Numbers

We understand that each project is an important investment to our clients, no matter how large or small; throughout the course of your project, our professionals will share valuable foresight on cost-effective options and value-driven solutions.

Determine the order of operations

To help protect the value of your commitment to energy, resources, and capital, we prepare a comprehensive, customized operation and maintenance manual that contains pertinent information and instructions relating to virtually every element of your finished project.

Our clients have always found this service essential in maintaining fiscal integrity and are pleased with the results.


We’ll take it from here. We’ll design and create your Colorado construction project from start to finish.

With this simple yet powerful strategy, we have grown to become one of Colorado’s leading general contractors. With collaboration and accountability as the cornerstones of our business, our mission has always been to establish and keep our clients’ trust. After all, they deserve nothing less than the most discerning attention to detail, quality and value.

As a result, 90% of Calcon’s projects are with repeat clientele.





ROC 323046


This is a unique website which will require a more modern browser to work!

Please upgrade today!