About a dozen parents said Monday that city and school officials should support a plan to borrow $70 million to upgrade four elementary schools in Portland.

The proposal, if approved, would have to be sent to the voters for their approval.

“It’s a large number, but it’s necessary,” said Jeanne Swanton, a parent with the advocacy group Protect Our Neighborhood Schools. She ran down a list of maintenance issues at the schools, adding “It’s not OK” after each item.

“How do we think this is acceptable?” Swanton said during a public hearing at City Hall at the first meeting of the school facilities ad hoc committee.

The committee was created July 6 by the City Council after the school board voted to recommend that the council send to voters a referendum on a $70 million bond issue to rebuild Presumpscot, Longfellow, Lyseth and Reiche elementary schools.

Supporters had hoped to get it on the November ballot, but the councilors said they needed more information before putting the issue before voters.

On Monday, councilors and School Board members went through a list of questions and issues, such as data on tax rates, school size and enrollment in surrounding communities.

Councilors also have asked for details on how the borrowing would affect the city and school budgets, and Portland’s property tax rate. Seven of the nine councilors’ votes would be needed to authorize the referendum.

Councilors said they want to know if it might be possible to seek funding from the state to renovate one of the schools, or whether it would be feasible to expand the Ocean Avenue Elementary School to accommodate some of the students from the four schools.

The committee said its next meeting will be on Wednesday, Aug. 3, from 5-8 p.m., and begin at Presumpscot.

Mayor Ethan Strimling said the ad hoc committee would schedule a second meeting before the end of the month to tour the remaining two schools.

The four schools have not had significant investments since they were built 40 to 60 years ago. Several schools do not comply with the Americans with Disabilities Act and the buildings are not secure.

Supporters say the $70 million would largely be spent on practical fixes, like installing functional heating and windows that open, making schools accessible for all users, eliminating trailers for classrooms and easing severe overcrowding. At one school, the social worker is in a windowless closet. Critics say it’s too much money and some of the renovations are more luxury than necessity, such as extra storage and new parking lots, roads and fields.

On Aug. 30, consultant Oak Point and Associates will present the renovation plans to the ad hoc committee, and in September the committee will review the answers to its questions and deliberate, Strimling said.

Once the committee has a final recommendation, it sets off another chain of events.

If the ad hoc committee’s proposal is different from the school board’s $70 million bond recommendation, the committee’s proposal will go back to the board, which must review it and then send a new recommendation to the council.

At that point, the council would refer it to the finance committee before taking it up.

Correction: An earlier version of this story had an incorrect time and place for the committee’s next meeting.