James Hardie Industries PLC (JHX) saw its stock plummet 5.38% during Wednesday's trading session, as investors reacted to the company's disappointing fourth-quarter results and cautious outlook for fiscal year 2026. The building materials supplier's gloomy forecast, particularly for its North American market, sparked concerns about future growth prospects.

In its latest earnings report, James Hardie revealed that its Q4 adjusted earnings per share came in at $0.36, meeting analyst expectations. However, the company's revenue of $971.50 million fell short of the anticipated $994.80 million. More worryingly, management's updated FY 2026 outlook caught investors off guard, projecting market volume contractions in North America, including a fourth consecutive year of declines in large-ticket repair and remodel activity.

Adding to investor concerns, RBC Capital Markets analyst Matthew McKellar noted that James Hardie's comments on repair and remodel markets being worse than new construction were "somewhat surprising." The company's net debt also raised eyebrows, with Barrenjoey analyst Brook Campbell-Crawford pointing out that it was approximately $80 million higher than consensus expectations. This increased debt level is particularly significant as James Hardie prepares to acquire U.S. rival AZEK in a cash-and-stock deal worth $8.75 billion.