The business prospered and expanded. It became Canada's leading publisher of sheet music, and initially had the sole right to publish copies of the Maple Leaf Forever. The company also opened branches in other cities across Canada. As well as continuing to import pianos, in 1890 the firm opened its own factory in Toronto and quickly became one of Canada's best known domestic piano brands.
Nordheimer became a prominent member of the city's commercial class, serving on a number of corporate boards. In 1871 he married Edith Boulton, who was from a prominent Toronto family that had played a leading role in the Family Compact and had built The Grange. That same year Nordheimer completed work on a massive home named Glenedyth. It was located on Davenport Hill, near James Austin's Spadina. While the house was demolished in the 1920s, the ravine running by the site is still known as the Nordheimer Ravine.
Nordheimer remained head of the company until his death, when the firm was taken over by his nephew Albert. Upon his retirement from the business in 1928, the firm was taken over by Heintzman & Co.