Meanwhile, about 44 percent of the construction workforce is age 45 or older and nearly one of every five construction workers is 55 or older, according to U.S. Census Bureau statistics.
On immigration reform, the group wants protections for immigrants already in the country and higher caps on the number foreign workers temporarily allowed into the country to work on construction projects.
"Unless there is action soon on these fronts, the construction industry in Colorado and across the country will face worker shortages with increasing frequency," Ken Simonson, the association's chief economist, said over hammering and the whirring of a drill at Denver's Union Station.
"These shortages have the potential to undermine broader economic growth by needlessly delaying and inflating the cost of construction and development," he said.
The station in the city's trendy lower downtown neighborhood is being renovated and a hotel and shops are being added along with commuter rail and bus service.
The group picked Denver for the announcement because it has been one of the top 10 metro areas for construction hiring in the past year. Simonson said Colorado's oil and gas industry is one of the main customers for new construction, but added that the industry is also competing for the same workers as builders.
Two union electricians working on a train platform said they saw the need for more training for future workers, noting that people been brought in from Nebraska and Oregon to finish the construction project. However, they said training programs offered by their union, the United Brotherhood of Electrical Workers, worked well and paid workers as they trained.
Electrician Shawna Smith said she worked as a teller for a credit union before deciding she'd rather work outside with her hands. She said she was surprised to work with new apprentices who didn't even know how to use a power drill or a ratchet set.