The two brownstones at 276 and 278 Newbury St. will be combined to create three New York-style apartments on the upper floors while keeping the two lower levels as commercial space.

In the early 1880s, as the Back Bay was being developed, housewright Silas Merrill built a row of 14 townhouses between 254 and 280 Newbury Street on land owned by George Wheatland Jr. The architect, according to Bainbridge Bunting’s “Houses of Boston’s Back Bay,” was G. Wilton Lewis.

The houses are on the south side of Newbury Street, between Fairfield and Gloucester streets.

In the mid-1920s or so, commercial activity took over the streetscape, and Newbury Street evolved into high-end shops, art galleries and cafés as well as offices.

Now, however, in the 21st century, properties are returning at least in part to residential use.

In particular, the two brownstones at 276 and 278 Newbury St. will be combined to create three New York-style apartments on the upper floors while keeping the two lower levels as commercial space.

Lisa Rainis of Otis & Ahearn Real Estate is marketing the three residential condominiums, whose address will be 276 Newbury.

“These homes will have big floor plates, three bedrooms, outdoor space and parking,” said Rainis. Their 44-foot-wide frontage along Newbury Street is unusual, and their location is prime, close to the Prudential Center and nearby restaurants and specialty stores, she said.

The developer is Centremark LLC of Boston, who was part of the team that built 4-6 Newbury St. five years ago. The new building, which replaced a six-story garage, houses the prestigious French design house Chanel and four luxurious homes.

For 276 Newbury, the architectural firm is Margolis + Fishman of Cambridge. Celebrity interior designer Ally Coulter has created illustrative renderings, using rich images of furnishings from Fendi Casa, for marketing these homes.

The base floor plan for each of the three condominiums will include a spacious living room that will flow into a dining room that will be open to a study. These three rooms will overlook Newbury Street.

A significant feature will be a raised gas ribbon fireplace in the living room, which will be set into a wood-paneled wall. The long stone hearth will be Italian black marble with gold veins.

Adjacent to the dining room, the open chef’s kitchen will include a center island that will house a microwave and a convection wall oven, next to a refrigerator. Against an interior wall will be a four-burner induction cooktop with hood and a deep sink. The appliances will be from Miele. The counters will be polished Quartzite, and the cabinetry will be custom-designed.

Off the study will be a powder room with polished porcelain walls and a matching tile floor in a natural finish.

The bedrooms will be at the back of the unit. Two of them will be accessible from the foyer, while the master bedroom will be accessible from a corridor from the living room.

The master bedroom will have a walk-in closet and a spa-like en suite bath with a double vanity, a commode room with a wall-mounted toilet, a glass-enclosed shower and a deep, oval-shaped stand-alone soaking tub. Another bedroom will have a smaller walk-in closet. A second full bath will include a combination tub/shower and a single vanity.

Each condo will have a laundry with a side-by-side Electrolux steam washer and dryer.

Unit 1, which will have about 2,000 +/- squae feet of living space, also will have exclusive use to a 530-square-foot deck and an outdoor parking space. It is listed at $4,250,000.

Plans for Units 2 and 3 will capitalize on additional space on the copper-clad penthouse level which will be split to offer each home a huge media room with a full bath and a private roof deck. These condos with approximately 2,500 +/- square feet of space and two parking spots have been priced at $5,500,000.

Options will be available as well. Units 2 and 3 could have an additional fireplace in the media room and on the roof. For Unit 2, the roof will be accessible via the direct-access elevator. For Unit 3, a staircase will give access to the media room.

These two condos also could create a second walk-in closet in the master bedroom, reducing the sleeping area in size, and replace a walk-in closet in the second bedroom with an en suite bath. Prices would be adjusted.

In addition, the study in each condo could serve as an additional bedroom, said Rainis.

Throughout each home, three-inch-wide rift-sawn white oak flooring will be used, laid in a herringbone pattern, except in the baths and the mechanical rooms, which will have porcelain tile. The ceilings will be about nine feet tall.

The residential entry at 276 Newbury will feature an elegant lobby. The walls and floor will be stone – light gray on the walls and dark gray on the floors – and the elevator will have front and rear stainless steel panel doors. The main staircase will have solid mahogany risers and treads.

The brick exterior will undergo renovations as well. Most noticeably will be the changes for the retail spaces at 278 Newbury St. An area at the front of the buildings will be excavated, the lower level windows will be extended and new retail entrances will be added. The plaza area will be topped with bluestone.

Construction is scheduled to begin in February, and it will take about four months to complete the shells of the residences. Completion is planned for December 2018.