An overall view of the Silver Spring Transit Center on Aug. 12, 2014, in Silver Spring, Md. (Yue Wu/The Washington Post)

The Montgomery County Council unhappily approved an additional $21.2 million to complete repairs to the Silver Spring Transit Center on Tuesday, with one member asking how much it would cost to demolish the beleaguered bus hub, now four years behind schedule and $50 million over budget.

County officials requested the money last month for construction of more than 200 new concrete beams and steel supports. The additional funds are also needed to finish off a layer of latex-modified concrete to strengthen roadways that will accommodate hundreds of buses each day.

The extra money brings the cost of the facility, plagued by cracks and other construction and design flaws, to nearly $14o million.

General Services director David Dise, lead county official overseeing the project, offered no specific opening date but said repairs would be complete “by late May, certainly in the spring.”

After the county is done, Metro, which will operate the center as part of its regional bus and rail system, will have 60 days to formally accept the facility.

Dise’s forecast drew a stiff response from Council President George Leventhal (D-At Large), who said some county taxpayers are so deeply frustrated with the delay that they advocate tearing down the building.

“Mr. Dise, a growing number of my constituents don’t believe anything you say anymore,” Leventhal said. “And I’m hearing from constituents that they think the promises are covering up a structurally-flawed building that ought to be torn down, that we ought to declare a loss and give up.”

He asked Dise for a “rough, seat-of-the-pants estimate” of demolition costs, not because he supported the idea but because he’d been frequently asked by residents.

Dise said he would try. But after the council session, he said he had been advised by county attorneys to avoid hazarding such a guess in public because of the impact it might have on whatever lawsuits the county files against contractors to recover costs.

Dise said the repairs have made the center “a sound building and not an unsafe building anymore.” But he said that winter weather, the availability of specialized equipment and lengthy deliberations on the best way to fix the facility all added to the delay.

“The implementation of those solutions has taken longer than we would like it to take. And that is all I can say,” Dise said.

About half of the $21.2 million will be revenue from the sale of general obligation bonds. The balance will be drawn from completed capital projects with funding surpluses, or projects underway but delayed.

“I’m deeply unhappy about it and every council member sitting up here is deeply unhappy about it,” Leventhal said. “And I know you are too, Mr. Dise.”