For nearly eight decades, County Materials Corporation has built more than concrete products — it has built relationships, careers and communities. What began in 1946 as a modest, family-run operation in central Wisconsin has grown into a multi-division manufacturer spanning seven states, employing more than 2,000 team members and serving a wide range of infrastructure and construction markets.
Yet despite its size and reach today, the company’s foundation remains rooted in the same principles that sparked its creation: listen to customers, invest in people and deliver quality you can stand behind.
As County Materials celebrates its 80th anniversary, that balance of tradition and forward-thinking continues to define its path.
The story of County Materials begins in the post-World War II era, a time marked by rapid growth and rebuilding across the United States. In Marathon, Wisconsin, the company’s founders recognized a pressing need for reliable, locally produced concrete materials to support that expansion.
Starting with a single manual concrete block machine, the business focused on supplying concrete masonry units, sand and aggregates to local builders, farmers and contractors. The operation was small, but the mission was clear: meet the needs of the community and earn trust through hard work and consistency.
Those early years established a blueprint that still guides the company today. Close relationships with customers — many of whom were neighbors and friends — helped shape a culture centered on responsiveness and reliability. The emphasis wasn’t just on producing materials; it was on solving problems and supporting growth within the communities they served.
That customer-first mindset proved to be a powerful driver as the company expanded beyond its original footprint.
Strategic Growth Across Decades
Over time, County Materials evolved from a single-product supplier into a diversified manufacturer with a broad portfolio of concrete solutions. Each decade brought new opportunities — and with them strategic investments that expanded both capabilities and reach.
A key turning point came in 1972, when the company entered the precast concrete market. This move marked the beginning of a long-term shift toward more engineered and specialized products. In the 1980s, the addition of concrete pipe production further strengthened its position ininfrastructure markets.
By the early 2000s, County Materials had grown significantly, including expansion into new geographic regions such as Florida. Around the same time, the company was selected to manufacture precast segments for the Hiawatha light rail transit tunnel in a high-profile infrastructure project that demonstrated its ability to deliver on complex, large-scale work.
“That project really put us on the map,” County Materials’ Executive VP of Marketing and Communications, Rebecca Sonnentag, explained. “It showed we could scale and support highly visible infrastructure projects.”
Since then, the company has continued to build on that momentum. Investments in advanced facilities — such as its Janesville, Wisconsin location — have enabled the production of prestressed and structural components, while organizational growth has led to the development of multiple divisions, including precast, prestress and ready-mix operations.
Today, County Materials operates more than 40 locations, including manufacturing plants, quarries, retail sites and offices, all working together as part of a unified family of companies.