Employees at the Armstrong World Industries floor plant, like Phillies fans, have endured decades of disappointment.

But both groups finally know what it feels like to win the big one.

Armstrong said today it has picked the Dillerville Road plant to begin making a popular kind of fiberglass-backed residential flooring it now imports.

The $25 million investment will not add jobs to the 200-employee site.

But it ensures that the plant, which has lost hundreds of jobs over the past two decades, will stay open for the foreseeable future.

"This prolongs the life of the facility," said union leader Joe Rumberger. "It's an exciting time right now."

Armstrong now makes the fiberglass-backed residential sheet product only at its plant in Teesside, England.

The fiberglass-backed flooring, sold under the CushionStep brand, is a hot seller in this country, posting double-digit sales gains for several years.

So Armstrong decided several months ago to make the sheet flooring in the United States too, to shave shipping costs and delivery times.

But where?

The company weighed whether to produce it at the Dillerville Road plant, to build a new plant somewhere to make it, or to have an outside firm manufacture it for Armstrong, union leaders said.

Today Armstrong said the local plant &tstr; where felt-backed residential sheet flooring is made &tstr; won the job due to its stellar track record.

"The experienced work force there, the remarkable job they've done improving cost and quality, the fact that the plant is well-known throughout the industry for producing high-quality sheet flooring products" all played a role in the decision, said spokeswoman Jen Johnson.

"They have great know-how and we have the manufacturing infrastructure already in place that we can leverage," she added.

When the upgrade is finished, the local plant will be "the most technologically advanced" plant of its kind in the world, said Armstrong.

The first fiberglass-backed vinyl sheet product is due to come off the production line in the first quarter of 2010.

Good news such as this has been rare recently for the Dillerville Road plant.The plant, which employed more than 3,000 people in the early 1970s, has been downsized numerous times since then as Armstrong sought to cut costs amid shrinking demand for vinyl flooring overall.

The most recent major cut came in 2004, when Armstrong disclosed it would stop making commercial flooring there, a move that eliminated 450 jobs.

As part of that decision, Armstrong shut down the Liberty Street side of the sprawling complex; those buildings since have been razed and will become the site of athletic fields and medical offices.

Armstrong consolidated what was left &tstr; residential flooring production &tstr; on the Dillerville Road side of the property, spending $8 million to outfit buildings there for their new use.

Now, four years later, Armstrong is increasing its commitment to the site dramatically.

Union leaders said Armstrong will install a new single, long production line to make the fiberglass-backed product, replacing the four separate lines used to make felt-backed products.

"It will be absolutely amazing," said Rumberger, president of United Steelworkers Local 285, which represents the plant's production workers.

Initially, the old lines will keep running as the new line goes in. But in late 2009, the old lines will be shut down and removed as the installation of the new line is completed.

The new flooring will be physically different from the current product in two key ways, explained Rumberger and Local 285 recording secretary Don Rogers.

As its name specifies, it will have a fiberglass backing, which is thinner, stronger and lighter than felt backing, they explained.

Also, the designs on the flooring will be printed in water-based ink, which offers environmental advantages over the oil-based ink used on felt-backed flooring.