Gibraltar Industries (ROCK 19.61%) stock had soared a solid 20% through 10:20 a.m. ET after crushing earnings forecasts in its Q4 report this morning.

Heading into the quarter, analysts forecast $0.91 per share in profit on $307.9 million in sales for the industrial conglomerate. Gibraltar actually earned $1.50, despite sales falling a bit short of expectations at $302.1 million.

What does Gibraltar Industries do?

A few words of introduction may be in order to this very diversified small-cap industrial company. Gibraltar describes itself as "a leading manufacturer and provider of products and services for the residential, renewable energy, agtech, and infrastructure markets."

So what does Gibraltar Industries do? Gibraltar builds bridge parts for one thing: expansion joints, joint seals, and bearing assemblies. Gibraltar builds home construction parts, everything from mailboxes to gutter covers to roof vents. Relatedly, Gibraltar makes mounting systems for solar panels on roofs. And in agricultural technology, Gibraltar builds environmental systems for projects such as greenhouses, including irrigation, lighting, and dehumidifying systems.

How well does Gibraltar Industries do it?

Despite its many activities, Gibraltar seems to be doing most of these things pretty well. While sales declined 8% year over year in Q4, the company's earnings more than doubled, up 138% year over year. Renewables sales declined 20%, and lost money in the quarter. But earnings improved in infrastructure, agtech, and residential.

Looking ahead, Gibraltar forecasts "growth, solid margin expansion, and strong cash flow generation across the business" in 2025, with more than $1.4 billion in sales and earnings between $4.25 and $4.50 per share. It's easy to see why investors are excited today. At a price-to-earnings ratio of only 16, the stock is worth keeping an eye on.