CHICAGO  The 250 workers who staged a December sit-in at a Chicago window factory to protest losing their jobs were celebrating Thursday, after another window manufacturer announced plans to reopen the plant and start hiring back the displaced workers within months.

The sale of what had been Republic Windows and Doors to a California company, Serious Materials, for $1.45 million, was completed in bankruptcy court this week, with company officials promising United Electrical Workers Local 1110 to rehire all the laid-off workers at their former rate of pay.

Image Armando Robles, left, and Melvin Maclin, workers at the window factory who are to be rehired. Credit... Amanda Rivkin for The New York Times

“We see this opportunity to expand our operations in direct relation to the stimulus package, which includes the greening of federal buildings and the weatherization assistance program,” said Sandra Vaughan, the chief marketing officer for Serious Materials, which also manufactures energy-efficient windows and building products in Boulder, Colo., and Vandergrift, Pa.