James Hardie has finally given the market something it hasn’t seen in a while: a reason to lean in instead of head for the exits.

After a bruising run through 2025, the building products giant has surged 13.74% over the past five trading days, climbing from $32.75 last Friday to $37.25 at Friday’s open, as investors digested its third-quarter FY26 results.

It’s still a long way from the near-$60 highs of 2024. But there's growth on the cards, at least.

What changed?

The headline numbers were strong, at least at first glance, beating analyst expectations on Wall Street.

Net sales for the December quarter came in at US$1.24 billion, up 30% on the prior year. Adjusted EBITDA rose 26% to US$329.9 million. Operating income, however, actually fell 15% to US$176.2 million, with margins compressing sharply to 14.2% from 21.6% a year earlier. Net income halved to US$68.7 million. On a statutory basis, this was not a blowout quarter.

The key difference lies in the troubled and controversial AZEK acquisition, which closed on July 1, 2025. The quarter’s 30% sales lift was driven largely by that inorganic contribution. In Siding & Trim, historically Hardie’s engine room, organic net sales were actually down 2%, as weaker volumes offset price gains.

Volumes in exterior products declined mid-single digits, with single-family down high-single digits in the US South. Those sales slippages are being felt particularly in the American South - markets that have been hit by affordability pressures and elevated inventory.

But despite some sluggish sales numbers, investors seem to have decided that the worst may be behind it.

Why the price increase?

First and foremost, James Hardie moved its guidance in the right direction. Against a fragile housing backdrop, even a modest upgrade signals stabilisation. Management lifted full-year FY26 net sales guidance for Siding & Trim to US$2.953–2.998 billion (from US$2.925–2.995 billion). Total adjusted EBITDA guidance was nudged up to US$1.232–1.263 billion (from US$1.20–1.25 billion).

Second, cost efficiencies from AZEK are tracking ahead of schedule. Management reiterated confidence in hitting a US$125 million "cost synergy" target. That matters, especially as integration risk was one of the market’s lingering concerns after the deal.

Third, cash flow remains solid. 

Three reasons when taken together might be giving investors some hope that the company is headed for more growth going forward.