PITTSFIELD — The school administration is moving quickly to secure a spot in line for possible state aid to upgrade Pittsfield High School, even as city leaders warn they may lack the borrowing capacity for a full-scale construction project.

Making that happen will require some logistical gymnastics, the School Building Needs Commission learned Tuesday. The application deadline to submit a "statement of interest” to the Massachusetts School Building Authority for potential improvements is April 17.

Before it can be handed in to the state, however, the plan requires endorsements from the City Council and the School Committee. That means the paperwork must be finished by Thursday so it can be reviewed at a special commission meeting Monday and included on the City Council and School Committee agendas for next week.

What’s more, it’s not clear that the core state school building program would be appropriate to fund updates to the 95-year-old building. Mayor Peter Marchetti said the city lacks the borrowing capacity to take on another school construction project and is in favor of pursuing the state's “accelerated repair” program instead.

"We have been advised by our city auditor or that we're at our borrowing capacity from the operating budget standpoint. So I have concerns of moving forward," he said.

While willing to support the school securing its place in line for funding, "when we get to the point in time where it's time to make financial decisions, the city may have to reevaluate our position," he said.

The Massachusetts School Building Authority funds a percentage of school construction projects, with communities paying the difference. For Pittsfield, the state picked up 80 percent of the bill for Taconic High School, and is set at 78.9 percent for a new elementary school at the Crosby Elementary School campus.

Interim School Superintendent Latifah Phillips, who announced last month that the district will pursue getting Pittsfield High onto the list of potential future projects, is interested in moving forward with this step because the next application window for state funding won’t come around for another two years.

Joining remotely, Phillips acknowledged that financing any work at Pittsfield High would need to be “carefully considered.” But she also said she wants to know more about Pittsfield High’s condition, including what other potential headaches the 95-year-old building might have in store.

Pittsfield High School underwent a renovation and addition in the mid-1970s, including the construction of Moynihan Field House.

In theory, the “accelerated repair” program — which is helping to pay for roof and window replacements at McCann Technical School in North Adams — would be used to address the building’s inefficient windows, the pipes connecting the school’s brand new boiler to classrooms, and possibly the roof.

The accelerated repair program is intended to help extend the life of school facilities and promote energy efficiency. However, its terms and conditions state it will not provide grants for facilities that “[have] more extensive capital repair needs beyond repair or replacement of the roof, windows/doors and/or HVAC system.”

While Pittsfield High’s new boiler is state-of-the-art machinery, the nearly century-old pipes connected to it have corroded with time, greatly reducing their capacity to move heat through the building. What’s more, many of those pipes are hidden behind walls.

City building maintenance director Brian Filiault warned that tracking down and replacing the high school's old pipes would likely involve tearing apart walls. That could lead to unanticipated abatement costs, depending on what’s behind those walls.

“We're probably in the $35 to $40 million range,” Filiault said. “But then what I mean by that is just the minimum. If you want to get into the whole thing and do it properly, it’s a much bigger project.”