American Standard has been a ubiquitous name in America’s kitchens and bathrooms for more than 140 years, but it used to be part of a much larger conglomerate that also included large HVAC and vehicle controls divisions. By early 2007, however, the company listened to the Wall Street sirens and launched a breakup plan that would include the sale of its kitchen and bath unit to the highest bidder (the vehicle controls unit became publicly-traded WABCO, while the HVAC unit was sold to Ingersoll-Rand).

Prospective bidders quickly learned that the kitchen and bath unit was “American” in name only, losing a bundle stateside while growing rapidly in Asia and Europe. In fact, it was expected that the ultimate winner would effectively shut down the American operations.

Sun Capital had been paying careful attention to the process, in large part because it already owned a pair of much smaller U.S. fixture-makers: Crane Plumbing and Eljer Plumbingware, both of which Sun acquired in 2005. When Sun learned that the American Standard process was down to just Bain Capital and SAC Capital, it went to Bain with an offer.

“We contacted them on a Friday when final bids were due on a Monday,” recalls Sun Capital co-CEO Marc Leder. “They were valuing the American business at zero, or maybe even a bit less because of what it would cost to shut it down. So over that weekend we agreed to pay $130 million for a majority stake in the Americas business, which Bain took and added it onto its bid for the global business and outbid SAC. We have them an ironclad agreement that if they closed on the larger deal, we’d close simultaneously on the Americas piece.”

Bain won the overall deal for $1.75 billion, and would rename the Asia and European business Ideal Standard. The $130 million carve-out of American Standard was structured with $50 million of equity — of which Sun put in slightly more than Bain for a 51% ownership stake. The remainder was debt.

Sun’s investment thesis was that American Standard had a lot of excess capacity, making the right products in the wrong places. For example, it was making certain low-volume, high-margin products in Mexico that would be better made in the U.S., and some higher-volume, lower-margin products that it thought should be made in Mexico. Sun also felt that the company was not doing nearly enough with product innovation, particularly when compared to market leader Kohler.

So Sun made major changes, some of which included layoffs. In 2008, it folded Crane and Eljer into American standard — opting not to do so earlier because each of those businesses were in rough shape when originally acquired by Sun.

“Both were heavy turnarounds, and it’s almost impossible to merge two of those businesses while fixing them,” Leder explains. “It’s better to merge once everything is doing well, so you can really benefit from the synergies.”

Two years later in merged in a small portfolio company called Decorative Panels, and also acquired a complementary business called Safety Tubs. And when the bond markets returned in 2011, Sun completed a $187 million high yield offering that repaid all of American Standard’s debt.

Much more quietly — as least to the outside world — Sun also was slowly accumulating ownership in American Standard. Not only via the Crane and Eljer mergers, but also through the add-on acquisitions that Bain wasn’t interested in helping to finance. Maybe because its Ideal Standard purchase hadn’t gone as well as expected –with Bain selling off the Asia operations for just $150 million in 2009, and also choosing to restructure the remaining European group.

By the time Sun began talking with LIXIL about a sale earlier this year, the firm held more than a 75% interest.

The final sale price of $542 million represents well over a 2x return on Sun’s original investment (including the merged portfolio companies), and a 13x EBITDA multiple.

“We think we’re very early in what will be a long and signifciant period of building product and housing growth in the U.S.,” Leder says. “So we asked LIXIL to pay us today what it will be worth in a couple of years, or we would wait and later hire an investment banker of take it public.”

LIXIL chose the former, valuing American Standard at a 40% premium to where Sun had valued the company at year-end 2012. But Leder’s prediction may have come true, since American Standard’s EBITDA actually grew by 20% between the time LIXIL signed its letter of intent and the time it signed the actual acquisition contract.

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