Boone County officials are expressing shock over the abrupt closing of a prominent Whitestown manufacturer that employed an estimated 250 people in the Anson development near Interstate 65 northwest of Indianapolis.

ASI Limited, which makes exterior enclosures for large buildings, informed employees by letter on Dec. 30 that the company was shutting down because it was no longer profitable.

In a statement, ASI said: “Management is currently reviewing its financial viability moving forward. It is hopeful that we can re-commence operations sometime in the near future.”

The high-profile portfolio of work ASI has built through the years made the closing even more difficult to understand for Dax Norton, director of the Boone County Economic Development Corp.

ASI makes curtain walls and exterior claddings for large projects throughout the country. Its work in downtown Indianapolis includes buildings such as the 33-story JW Marriott hotel, Lucas Oil Stadium and Central Library.

“This was just as much of a surprise to [employees] as it was to anybody else,” Norton said. “Everything seemed very strong.”

Norton said he has attempted to contact company President Ken Smith via telephone and e-mail to gather more information but has been unsuccessful.

Smith also did not return calls from IBJ.

ASI’s website says the company was chosen to design 219,000 square feet of weathered steel plates for the new Barclays Center in Brooklyn, where the New Jersey Nets are set to begin playing next season. Whether ASI finished the job is unclear.

With $65.2 million in revenue in 2010, ASI ranked as the sixth-largest glazing contractor in the nation, according to USGlass Magazine.

ASI occupied about 200,000 square feet in Anson and was one of three large employers in the development. Amazon has about 1 million square feet and about 850 workers while Medco occupies 400,000 square feet with roughly 450 employees.

Founded in 1989, ASI moved from Park 100 on the northwest side of Indianapolis in 2008 to the Whitestown Industrial Park in Duke Realty Co.’s Anson development.

Whitestown helped lure ASI with a property-tax abatement that is set to expire in 2017, Norton said.

He’s confident Duke Realty ultimately can attract a tenant to fill the space, if ASI closes permanently.

“The demand [for industrial space] is huge,” Norton said. “We have no industrial space available in Boone County. We have spec space, but as far as existing space, there is none.”

Meanwhile, an Indiana Department of Workforce Development spokeswoman said ASI did not file the required paperwork notifying the state of the plant closure.

Companies with at least 100 workers that expect to close or lay off 50 or more employees must notify the state 60 days prior to the action. The requirement falls under the federal Worker Adjustment and Retraining Notification Act of 1989.

Exceptions include “unforeseeable” business circumstances and natural disasters.

Federal guidelines say a company can be fined $500 for each day it is in violation of the required notification. Affected employees or municipalities also can bring federal lawsuits against a non-complying company.