Reopening the Mosquito Lake School building may involve more than unlocking the door and turning up the heat.

Haines Borough public facilities director Carlos Jimenez said this week that it’s his understanding from the state fire marshal that the building’s sprinkler system would need to be brought up to code for the structure to reopen as a school. That would cost an estimated $160,000.

While the school was operating, its sprinkler system was effectively “grandfathered” into previous, less stringent requirements, Jimenez said.

The required work will include an additional water storage tank, a new supply line and extension of lines into a school multipurpose room and two classrooms.

The borough recently spent about $95,000 on the sprinkler system, including a replacement water tank, pumping station, controls, fixtures and extension of lines to two store rooms, a boiler room and a kitchen.

School board president Anne Marie Palmieri said this week that the additional costs for closing and reopening weren’t made known to her last April, when the school board decided to close the school.

Whether Mosquito Lake can be used as a community center without upgrading the sprinklers may depend on the number of people using the building at one time, Jimenez said.

At the school board’s January meeting, members expect to hear a report from superintendent Ginger Jewell on whether the requisite 10 students are there that are needed to open and fund the school as a separate site.

As the building has reverted back to borough ownership, the school district is only involved in the school issue peripherally at this stage, Palmieri said.