BANGOR, Maine — For the first time since Bangor’s downtown Freese’s Department Store shut its doors in 1985, its former headquarters should be fully occupied next spring.

Bangor Housing Development Corp. started a construction project on Sept. 9 that will convert the remaining vacant portion of the Main Street landmark — the bottom three floors on the Water Street side — into market-rate apartments and commercial space.

The first tenant, a Belfast-based juice bar and vegan cafe called The Juice Cellar, plans to open a second location in the building’s Main Street storefront in early November. Crews will punch out windows on the first and second floors of the Water Street side of the building and open up a second, smaller storefront along Water Street.

The second and third floors will be converted into 10 apartment units, including four one-bedroom, two two-bedroom and four studio units.

“If you want to live downtown, this will be a really cool place,” said Mike Myatt, executive director of Bangor Housing, during a recent tour of the property.

Bangor Housing Development Corp., a development wing of Bangor Housing Authority, is investing about $1.27 million in renovations to the three floors, including extensive utility work. The corporation is a nonprofit entity but has pledged to pay taxes on the property to the city.

The apartments are geared toward “young professionals or folks looking to downsize and come back downtown,” Myatt said.

He expects rents to range from about $800 for most studios and $1,200 for most two-bedroom units. Utilities will be included, Myatt said.

“Easy living,” Myatt said. “I just wanted people to have one price.”

Construction on those units should be completed and ready to rent by next spring.

Freese’s closed in 1985 after more than 90 years in business. The bulk of the building is occupied by the Maine Discovery Museum and 39 assisted living and elderly housing units on the top three floors. But portions of the bottom three floors not occupied by the museum have been either vacant or underused since.

In 2012, the city reacquired the property from Realty Resources Management, which was supposed to have developed the lower three floors, after that project never came to fruition.

Myatt said putting the last vacant section of the building back into use is a rewarding undertaking. People on tours of the building are always eager to share their stories about their time in the store when they were children.

“Everybody has a story about coming to see Santa or getting kicked off the escalator,” which was the only one in Bangor at the time, Myatt said.

Follow Nick McCrea on Twitter @nmccrea213.