Presales of 109 luxury condos in the $300 million Pierce Boston tower in the Fenway are averaging prices of $1,500 per square foot with 40 percent sold ahead of the projected spring 2018 occupancy.

A leasing center for 240 apartments located on the lower floors will open next year, said Leslie Cohen, chief operating officer for Samuels & Assoc. of Boston.

Samuels & Assoc. is partnering with Weiner Ventures of Boston and Chinese investor Landsea on the project being built on a 0.6-acre lot at the corner of Boylston Street and Brookline Avenue. A topping-off ceremony was held Friday.

Miami-based Arquitectonica designed the tower in its first Boston project, with interiors by Boston-based CBT Architects. The condos occupy floors 19 through 29. The 30th floor also will include an indoor “Levity Lounge” with amenity space next to an outdoor pool deck and private individually-owned sky cabanas.

The project also will include 20,000 square feet of ground-floor retail space and an outdoor art installation.

Samuels added condos to the project last year as the designs were updated with an additional six stories, making it the tallest building in the Fenway.

The tower is supported by 350 pilings driven up to 220 feet below ground, including 30 feet of bedrock. Construction manager John Moriarty & Assoc. needed to request a pile hammer driving machine from the mid-Atlantic region that was powerful enough to complete the 14 miles of piling work, President John Moriarty said.

“It was the hardest pile-driving job we’ve ever done in Boston,” he said. “We’re lucky because we have terrific geotechnical engineers in McPhail Assoc. (of Cambridge).”

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