Meghan Keneally Thomas Balsley at Monday’s meeting.

Members of Community Board 3 voted unanimously Monday night to oppose plans for an outdoor plaza at the new 51 Astor Place because of questions about whether the design provides enough space for the public and fits aesthetically with the surrounding neighborhood.

The board’s Planning and Land Use committee said that it will not endorse the plaza project unless changes are made that take into account the historic nature of the area around 51 Astor and other design issues, including the placement of benches.

Work is set to begin in the next few days, and the construction of the mixed-use commercial tower is set to last for 17 months.

After listening to a presentation by Thomas Balsley, the designer in charge of planning the outdoor space that will accompany the new building on Astor Place, members of the public were given a chance to address the board.

Speakers, many of whom were opposed to the design, raised a range of issues about the project from its look and aesthetics to what some said was its failure to account for the historic nature of the district.

“It’s like it’s from some other city,” said Marilyn Appleberg, who was a part of the group that discussed the initial plans for the building when they were approved in 2002. “I was really disappointed.”

A final discussion on the plaza project will occur at the full community board meeting on July 26.