For decades, DIYers and construction pros have picked up yellow and red bags of Quikrete concrete mix from the shelves of America’s big box stores like Home Depot and used it for everything from anchoring mailboxes to patching driveways and making outdoor benches and steps. That in turn has generated billions of dollars for the little-known company and the little-known family behind the brand.

But their time in the shadows may have come to an end. In February 2025, the privately-held building materials firm made a big splash when it paid $11.5 billion to acquire publicly traded competitor Summit Materials. The deal, which Forbes estimates boosted Quikrete’s revenue by around 50% to an estimated $12 billion, helped propel the Atlanta-based company onto Forbes’ first ever ranking of America’s Largest Family Businesses, published this week, at No. 43. Based on Forbes’ estimates, Quikrete is the 17th most valuable privately-held family business in America, making its founding Winchester family one of the country’s richest clans, worth an estimated $18 billion, thanks to their estimated 100% ownership of Quikrete.

“We’re proud of our heritage as an American, family-run company that has helped revolutionize the building and home improvement industries,” said Quikrete’s longtime former CEO Jim Winchester in a press release celebrating the company’s 75th anniversary in 2015. “From day one, my father Gene Winchester was driven to meet the needs of both contractors and homeowners with the highest-quality products at fair market value, and that commitment remains a core value of Quikrete today.”

That marked a rare public statement for the ultra-private Winchesters, who have managed to keep a low-profile despite building and owning a company that Forbes estimates is now more valuable than bigger-name family businesses like Nordstrom, Wawa and Kohler. Though a non-family member, Quikrete’s former president and chief operating officer Will Magill, has been CEO since around 2020, Jim Winchester, 82, served as chief executive until at least 2015 and still sits on the company’s three-person board, alongside his brothers Jack, 80, and Dennis, 77.

The Winchesters barely ever speak to the press, and little information about the family is available online, save for a few listings of roles with community organizations like the Buckhead Coalition in the affluent Buckhead neighborhood of Atlanta, or as current and former members of the board of their alma mater, John Carroll University in Cleveland. The family has also appeared in Federal Election Commission filings detailing their contributions to mostly Republican politicians and their political committees, the largest of which was a $103,000 donation by Dennis Winchester to the Trump 47 Committee in 2024. A representative for Quikrete and the Winchesters declined multiple requests for interviews and to comment for this story, telling Forbes that the family did not wish to be profiled for privacy reasons.

Quikrete got its start as a small building materials company called Maintenance Products, Inc. that was founded in Columbus, Ohio in 1940. But according to a company history published by Quikrete, its predecessor had “meager success and little direction.” That is until the man who would be credited as Quikrete’s founder, former aeronautical engineer Gene Winchester (d. 2003), joined as general manager a decade later.

According to an obituary his family placed in the Atlanta Journal-Constitution, Winchester, the son of a Tennessee coal miner nicknamed “Luppy," developed a love for aeronautics at age 10 in 1927, the year Charles Lindbergh completed the first non-stop solo flight from New York to Paris, sparking what became known as the "Lindbergh boom" in aviation. At age 19, Winchester moved to Glendale, California to study aeronautical engineering at a trade school operated by Curtiss-Wright Corporation, before going to work for the aerospace company in St. Louis. But after “many moves” in the industry and the births of five of his six children, Winchester was looking to settle down when he took a job at what was then known as Maintenance Products in the Buckeye State capital in 1950.

The following year, in 1951, Winchester helped pioneer the pre-blended, packaged concrete that would change construction forever and help create the DIY home improvement market, when he launched the company’s first branded product, Gemaco Quikrete. Competitor Sakrete (now part of publicly traded building materials giant CRH plc) apparently beat Maintenance Products to market, selling the first bags of dry concrete mix that only required adding water in 1936. But Sakrete still hadn’t been widely adopted 15 years later, and pouring concrete still almost always involved either a complicated, multi-part mixing process or delivery of wet concrete from a factory by truck when Winchester introduced his competing product. The latter process, known as “ready mix concrete” is still the standard for larger construction projects, but is impractical for the small-to-mid-size jobs that would become Quikrete’s bread and butter.

Likely realizing the potential for Gemaco Quikrete as the United States transitioned from the Great Depression to the post-World War II economic boom, Winchester “cobbled together the financing” to buy his employer, Maintenance Product Inc., and renamed it Quikrete in 1965. Then, after determining that a national distribution network would be critical to his product’s success, Winchester immediately hit the road, kicking off a geographic expansion that would grow the company’s footprint beyond Ohio to nearly 50 markets in the U.S. and Canada by the end of the 1980s.

“The actual product grouping dictated that you had to have local manufacturing, and of course, that turned into a very powerful distribution tool [across] the nation,” said son Dennis Winchester, a longtime former Quikrete executive, in a 2015 company video. “Very few people can deliver an 80 pound bag of concrete anywhere in the United States–Hawaii and Alaska included–in 24 hours or less. And we did that in the ‘60s and ‘70s.”

Dennis Winchester and his older brothers Jim and Jack all graduated from John Carroll University in Cleveland between 1965 and 1970, and went on to serve stints as members of the school’s board of directors. “Our parents sacrificed everything to make sure we received a Jesuit education,” said Jack Winchester in a report published by the university after the Winchester brothers donated $1 million for scholarships in 2014. “Now that my brothers and I are in a position to pay it forward, we feel investing in JCU is essential.”

After graduating from John Carroll, the Winchester brothers took over leadership of Quikrete from their father in 1981 and moved the company’s headquarters to Atlanta that same year, just three years after The Home Depot was founded in the same city. Then, in 1985, Quikrete ramped up the TV and print marketing blitz that would make its yellow and red bags of concrete famous, signing up five-time Emmy Award winning actor and comedian Don Knotts of The Andy Griffith Show as the company’s first corporate spokesperson.

In their more than three decades running the company as executives, the second generation of the Winchester family helped build Quikrete into the largest producer of packaged concrete and cement mixes in the U.S. and Canada, more than tripling the number of Quikrete manufacturing plants to over 90 by 2015, and beating out competitors like first mover Sakrete.

“Quikrete built up one of the first national brands for any concrete product, because of the distribution it had through big box and independent building material and lumber yards,” says Don Marsh, the longtime editor of trade publication Concrete Products. “It was an early model of operational excellence in a low margin product category, and I believe that the ability it had to serve the big box channels enabled it to expand and establish the scale that would set the table for other opportunities outside of packaged materials.”

Beginning around the early 2010s, the Winchester brothers also started diversifying Quikrete’s product offerings by acquiring other building materials companies like concrete block manufacturer Best Block; tile, stone and flooring firm Custom Building Products; and asphalt outfit Quality Pavement Repair.

Quikrete’s acquisition spree hasn’t slowed down over the past decade. In 2016, the company paid $1.1 billion to buy private equity-backed Contech Engineered Solutions, which builds infrastructure like bridges, retaining walls, and stormwater and erosion control systems. A year later, Quikrete bought the U.S. concrete pipe business of Mexican cement giant CEMEX for approximately $500 million. In 2022, Quikrete acquired publicly traded water and drainage pipe giant Forterra for $2.7 billion. Then came the massive, $11.5 billion Summit Materials acquisition in 2025, and, this February, another big deal in which Quickcrete exchanged nearly $3 billion of assets with publicly traded building materials giant Martin Marietta Materials. Those latest two transactions have pushed Quikrete into manufacturing the raw ingredients that are the primary components of concrete–namely the binding agent cement and so-called “aggregates” like stone, sand and gravel– and into the “ready mix concrete” business as well.

“That string of acquisitions since 2010 has transformed that whole brand from a very strong position in a low margin commodity sector of construction materials to an 800-pound gorilla across the board,” says Concrete Products’ Marsh. “Quikrete is a private company now very much in the league of [publicly-traded competitors] Martin Marietta, Vulcan, Amrize, CRH, Eagle Materials and Titan America.”

And despite the Winchester family’s disdain for publicity, Quikrete’s building materials have been used to restore landmarks including the Statue of Liberty, the U.S. Capitol Dome and Alcatraz as well as at sports venues like Fenway Park and Gillette Stadium. Quikrete also supplied six million pounds of materials used in the construction of the Georgia Aquarium in Atlanta, primarily funded by billionaire Home Depot cofounder Bernie Marcus (d. 2024).

All of that acquired growth has come at a cost. Thanks in large part to the Summit Materials acquisition, which was mostly debt-financed according to a report published by credit ratings agency S&P Global Ratings in January 2025, Quikrete now has around $13.7 billion of debt on its books requiring cash interest payments approaching $1.1 billion every year, according to credit ratings agency Moody’s Ratings’ most recent credit report, published in December.

Fortunately for Quikrete, the Summit acquisition also significantly boosted profits, with S&P Global Ratings noting in an early 2025 report that it expected the combined company to have pro forma EBITDA (earnings before interest, taxes, depreciation and amortization) of more than $3 billion. Forbes estimates that Summit Materials contributed about $1 billion of that total, based on the $732 million of adjusted EBITDA and $3.1 billion of revenue it reported for the first nine months of 2024 in the last financial statements it filed as a public company. That squares with S&P Global Ratings’ most recent report in November, which said it expected Quikrete’s revenue to rise between 50% and 60% in 2025, “buoyed by its acquisition of Summit Materials,” before sales growth normalizes at 3% to 7% in 2026.

“We put their operating margin as BAA, and you'll see in our methodology that that's a range of 15% to 20%, which is very powerful,” says Moody’s Ratings vice president of corporate finance Peter Doyle. “And you could imagine EBITDA is even higher than that. So operationally they're doing very, very well.”

In other words, Quikrete keeps on winning. And as Jim Winchester said in the 2015 video celebrating the company’s 75th birthday, before crediting his and his brothers’ employees in the field for Quikrete’s success: “Everybody likes a winner. And if you’re on the winning team, you’d like to stay with the winning team.”

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