BELFAST — By the narrowest of margins, the Planning Board has reduced the permitted size of the proposed Cedar Ridge apartment complex from 52 to 30 units.

The 4-3 vote to restrict development on the 5-plus acre parcel off Cedar Street to six units per acre was recorded a few minutes before midnight Wednesday, at the close of a marathon public hearing. The vote left those on the losing side aghast.

Camden developer John Morris designed the project with a density of 10 units per acre. The decision to reduce it to six per acre may scuttle the $4.5 million project.

Voting in support of lowering the unit density were acting Chairman Eugene Kirby, Terry Hire, Andy McClure and Dan Clark. James Roberts, John Marshall and Phil Crosby opposed reducing the size of the project.

“On that piece of land, in our estimate, you can only build six units per acre,” Kirby said Thursday.

Although the city’s zoning ordinance established that Planned Unit Developments (PUDs) “shall not” exceed 10 units per acre, Kirby emphasized that the ordinance was filled with the discretionary term “may” when describing the Planning Board’s authority to determine neighborhood characteristics and density.

“There are a lot of `mays’ in there, and I think it’s up to the discretion of the board to make those judgments,” Kirby said.

Roberts, who was on the losing side of the vote, said he was “in awe” of the board majority’s interpretation of the ordinance. Roberts suggested the hearts of his four colleagues overruled their heads, that their vote was pressured by the groundswell of opposition to the project.

“They took the best way out because of the crowd,” Roberts said. “I think the process was totally wrong. You’ve got to go by what the ordinance says, and they interpreted the ordinance the way they wanted to. It’s totally wrong, and it really ticked me off.”

The Cedar Ridge development came under fire from neighbors almost from the moment Morris announced his intentions. The Neighbors for Neighborhoods group was organized in response. Many of its members were among the more than 100 residents that attended Wednesday’s hearing. The group argued that Cedar Ridge was incompatible with the neighborhood, comparing the three-story, 26,000-square-foot building project to the former Crosby High School.

Kirby said he and other board members looked closely at the density of the neighborhood. A majority agreed that the existing residential zoning standard for the Cedar/Wight street neighborhood of a maximum of one two-family residence for each one-third acre was applicable in the case of Cedar Ridge.

“Going by that, you have six units per acre,” Kirby said. “It’s a discretionary thing, and one of the things the Planning Board may modify is space.”

Kirby said the board would resume its review of the project next Wednesday. Still to be determined, he said, was whether by being contained in one structure Cedar Ridge was at odds with the PUD requirement of a maximum 10 units per acre.

“I believe it should be spread out amongst the entire parcel instead of being up in one corner,” Kirby said. “We have to ensure a harmonious relationship with the adjoining community.”

Attempts to reach Morris were unsuccessful Thursday, but Roberts said he had informed him that “he wouldn’t be able to do the project unless he could have the full 52 units.” He added that, in his opinion, the board’s decision represented an “unjust use of the zoning ordinance” and predicted that “This is not over by a long shot. We’ll just see what happens next week.”