TOWNSEND -- The North Middlesex Regional High School new construction project has moved forward to the schematic design phase, and town boards are beginning to plan for the next steps in the plan's approval process.

Representatives of Symmes, Maini & McKee Associates, which is designing the facility, briefed town officials on the progress of the building project at a joint meeting of the School Committee, the School Building Committee and the Boards of Selectmen and Finance committees from Ashby, Pepperell and Townsend.

Lorraine Finnegan of SMMA said the school is designed to be energy-efficient to reduce energy costs and to meet students' needs with new technology.

"This is a minimum 50-year building," Finnegan said.

The new school would be slightly smaller than the old school, which is more than 20,000 square feet bigger than MSBA requirements.

The Building Committee is planning to host two community forums to brief the public on the project on Oct. 7 and Nov. 18 at North Middlesex Regional High School.

She also said the facility's parking lot would be concentrated to one side and access points to the road would be eliminated, allowing for more security.

The building committee's preferred option for new construction was approved by the Massachusetts School Building Authority at their July 31 meeting.

Alex Pitkin, senior vice president of SMMA, said building a new school was preferable to renovating the old school.

"We can get you into the new school a lot faster than with a phased renovation," Pitkin said.

The project is estimated to cost $90 million. Finnegan said she estimates that 58 percent to 60 percent of the eligible costs will be reimbursed by the MSBA. Costs that are not eligible for reimbursement include septic systems and leach fields, turf fields, building permits, moving costs and legal fees.

However, Finnegan emphasized that none of the cost estimates would be concrete until they go before the MSBA board.

"Until we get to the project scope and funding agreement, we won't know what the bottom line is," she said.

SMMA and the building committee are now in the schematic design phase of the project, which involves finalizing details of the budget, determining how classrooms will be grouped in the new floor plan and discussing what kinds of technology and furniture will be used in the new building, Finnegan said.

After the budget is finalized in late October or early November, the committee will again go to the MSBA for approval, before being voted on in the towns this spring.

Representatives from the three towns also discussed whether to hold Special Town Meetings around March, followed by special town elections, or whether to wait for May's annual Town Meetings.

Building Committee Chairman Rob Templeton said Special Town Meetings could move up the beginning of construction, which would help in meeting a planned September 2017 opening.

"If we can work it so we're not waiting until May to have the Town Meetings and votes, I think it would be beneficial," Templeton said.

But some town officials expressed concerns about breaking up the elections.

Melissa Tzanoudakis, chairwoman of the Pepperell Finance Committee, said it would be easier for taxpayers to make an informed decision if they can see the budget as a whole, rather than just the budget for the school project.

"It's easier for people to see how the entire bottom line will be impacted rather than piecemealing it out," Tzanoudakis said.

Townsend Town Administrator Andrew Sheehan brought up the point that holding too many elections may discourage people from voting.

"One thing to keep in mind is voter fatigue, which is something we've run into in the past," Sheehan said, citing the special elections that have been held statewide in the past few years.

No decision was made on the matter.