Careers
From a small excavation business to one of the country’s leading heavy civil general contractors, SEMA’s journey has been defined by bold moves, strong partnerships, and a commitment to delivering excellence. This is how it all started.
The Early Years (1962 – 1991)
A Foundation in Family
SEMA’s story starts with Ames Construction, founded by Richard Ames in Burnsville, Minnesota, in 1962. Richard, one of eight siblings, learned the value of hard work early, shaped by his father Chester’s unshakable work ethic and his mother Ruby’s dedication to family. As the business grew, so did the Ames family’s role in shaping the company.
Among them was Tom Ames, who joined the family business right after high school in 1966. But Tom had an independent streak. While his brothers stayed with Ames Construction, Tom struck out on his own in 1969, launching Tom’s Excavating, specializing in basement excavation and small civil projects.
That independence didn’t last long. In 1970, family ties called him back to Ames Construction, where he spent the next 23 years helping to grow the business. By the early ‘80s, Tom and his wife Lois Ann Ames moved to Denver to lead Ames Construction’s expansion into Colorado. It was here that Tom began forging new relationships and planting the seeds for what would become SEMA Construction.
One of those connections was Brad Spies, a project superintendent Tom first met in 1984 while working as a subcontractor. Little did they know, their partnership would help shape SEMA’s future.
As the 1980s ended, Ames Construction secured a major contract for Denver International Airport, a career-defining project where Tom played a key role. But by 1991, Tom felt the pull of independence once again. On the verge of his 46th birthday, he made a bold decision—it was time to step away from Ames Construction and build something of his own.
The Birth of SEMA (1991 – 1995)
Starting From the Ground Up
In 1991, Tom Ames founded SEMA Construction, starting with a focus on mass grading and underground wet utilities. For the first few years, SEMA operated primarily as a subcontractor, working alongside major heavy highway contractors in Colorado and New Mexico.
In 1995, Tom invited Brad Spies to join SEMA as a partner. Brad brought deep expertise in structural work, which expanded SEMA’s capabilities. Together, they transformed the company into a full-service general contractor, handling earthwork, utilities, and concrete structures. This shift gave SEMA a competitive edge, allowing them to take on larger and more complex projects.
Expansion & Growth (1995 – Present)
From a Family Business to a National Contractor
Over the past three decades, SEMA has grown from a small subcontracting firm to one of the country’s largest Heavy Civil General Contractors, with regional offices in Southern California, Colorado, Texas, Tennessee, and Florida. The company has tackled projects in both the public and private sectors, building a reputation for quality, innovation, and strong execution across multiple contracting methodologies, including CM/GC, CMAR, Progressive Design-Build, and Design-Bid-Build.
Though SEMA has expanded significantly, Tom Ames remains deeply involved in the business. He still visits project sites, connects with employees, and maintains the family-driven values that have been at the core of the company from day one.
Today, the next generation is carrying the torch. Tom’s son, Brett Ames, now serves as one of SEMA’s district presidents, ensuring that the legacy of dedication, integrity, and a relentless work ethic continues.
More to look Forward to
The SEMA Experience
