Today on Forbes, this family made an $18 billion fortune selling fast-drying concrete.

For decades, DIYers and construction pros have picked up yellow and red bags of Quicrete 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 Quicrete's revenue by around 50% to an estimated

$12 billion, helped propel the Atlanta-based company onto Forbes's first ever ranking of America's

largest family businesses, published last week, at number 43.

Based on Forbes's estimates, Quiccrete 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 Quicrete.

In a press release celebrating the company's 75th anniversary in 2015,

Quicrete's longtime former CEO Jim Winchester said,

quote,

We're proud of our heritage as an American family-run company

that has helped revolutionize the building and home improvement industries.

From day one, my father, Jean 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 Quicrete today.

That marked a rare public statement for the ultra-private Winchesters, who have managed to keep a low profile,

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