Work has started on the Onyx Residences, a $7 million mixed-use development that will be built downtown at the corner of Third and Convention streets.

The Onyx Residences will have 28 apartments on top of 5,600 square feet of commercial space. The apartments will range in size from 600 square feet for a one-bedroom unit to 1,100 square feet for a two-bedroom. Rents will range from $1,600 to $2,500 a month and include amenities such as fiber-based Internet provided by CenturyLink, DirectTV service and balconies overlooking the street.

Craig Davenport, who follows the Baton Rouge apartment market for Cook Moore & Associates, said the downtown apartment market had a 98 percent occupancy rate, in the most recent survey, which was taken in July. The average rent was between $1.57 and $1.60 a square foot for a one-bedroom apartment, well below the $2.67 a square foot the Onyx Residences is asking.

“There are just a small handful of apartments downtown,” Davenport said. But that will change soon.

The 65-unit development 440 on Third, at the site of the old Capital One bank building, is set to open in January. The 525 Lafayette residential development, which will include 85 luxury apartments and nine townhomes, is under construction next to the IBM Service Center. It will open in fall 2015, around the same time the Onyx is projected to open. And financing is in place for the redevelopment of the Commerce Building at Third and Laurel streets; plans are to have 93 apartments in the building.

Commercial Properties Realty Trust, which manages and develops the property holdings of the Baton Rouge Area Foundation, is handling the redevelopment of the Onyx and 525 Lafayette. Pre-leasing for units in the Onyx is set to begin in October.

The Onyx Building was opened in the 1950s and was the home of Rider’s Jewelry until the late 1970s. City Year occupied the building for several years, until it moved out in 2010.

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