PORTLAND — It is coming down to dollars and cents for the ad hoc School Facilities Committee.

The committee, led by Mayor Ethan Strimling and School Board Chairwoman Marnie Morrione, will meet at 5 p.m. Nov. 2 at the Merrill Auditorium Rehearsal Hall, 20 Myrtle St., to discuss the financial impact of a proposed $70.6 million bond to renovate and expand four city elementary schools.

On Oct. 6, the committee met for two hours at Casco Bay High School to review the Buildings for Our Future report by Oak Point Associates that details the estimates for fixes and upgrades at Longfellow, Lyseth, Presumpscot and Reiche elementary schools.

The report has formed the basis for the borrowing proposal forwarded by the School Board to the City Council in June, and was tailored to provide more details about the scope of work needed at each school.

Senior architect Tyler Barter led the presentation, noting estimated construction costs could increase by 23 percent by the time the work is completed, which is scheduled for 2022. The mean estimate is 18 percent, and increases are based from the time Oak Point was engaged by the School Department in 2013 to assess needs and improvements.

While the intent is to create equity in learning environments throughout city schools, Barter also detailed individual needs that can vary greatly between the four schools.

At Lyseth School, 157 Auburn St., and Presumpscot School, 69 Presumpscot St., plans call for adding second floors. The estimated costs are $1.26 and $2.8 million, respectively.

“(Expansion) is by far the largest cost item at Presumpscot School,” Barter said, estimated at $7.5 million of the total, which is approximately $16.1 million. Expanding the school would eliminate portable classrooms, and a second floor would help create space for a new pre-K program on the first floor.

“I’m not willing to spend an extra $2.8 million just to put a pre-K there,” Councilor Nick Mavodones Jr. said, suggesting pre-K could be added at another school to help reduce costs at Presumpscot.

Longfellow Elementary School, at 432 Stevens Ave., is the oldest of the four schools and least in need of expansion. Completed in 1952, it needs the most renovations, at an estimated project cost of $16.36 million.

“It really comes down the complexities of a multi-story building and the interface with Deering High School,” Barter said.

Plans call for installing an elevator at Longfellow to bring the school into full compliance with the Americans With Disabilities Act, which Barter estimated could cost $800,000. That estimate is tied into other needed mechanical improvements.

In all, renovation and reconfiguration work is estimated to cost $5.9 million.

Reiche, at 166 Brackett St., also need renovations, but committee members are still grappling with meshing the school’s open space approach to learning with the need to reduce noise and create separate space for special education and English language instruction.

Superintendent Xavier Botana summarized the goals.

“People want to keep the feel of Reiche as an open school, but as we have to do more interventions, there are places where people want less noise,” Botana said.

Of the $17.8 million project estimate, $8.4 million will be needed for renovation and reconfiguration, including adding interior walls and replacing underground steam lines. The report also calls for spending almost $600,000 for a solar- powered water heating system.

At Lyseth, the cost estimate is $20.21 million, with $7.7 million spent on expansion that would eliminate the use of portable classrooms.

Lyseth is now scheduled as the last phase of the project, although exterior work on playing fields could be done sooner. Barter said it is also unique in its scope.

“It is a little more aggressive on the part of demolition; we are taking out a part of the gym to build the new gym,” he said.

Committee recommendations are expected to be completed in mid-November, then sent back to the School Board. From there, the City Council Finance Committee will consider the bond proposal before it reaches the full City Council. Public comment will be heard along the way and before the council votes to place the bond on a referendum ballot.

A bond referendum is anticipated in late winter or early spring 2017.

David Harry can be reached at 781-3661 ext. 110 or dharry@theforecaster.net. Follow him on Twitter: @DavidHarry8.