HOLYOKE — Construction work on the city’s new, 550-student middle school is set to begin on schedule later this month under the supervision of general contractor Fontaine Bros.

The company, with offices in Springfield and Worcester, was the lowest qualified bidder out of seven companies that were pre-qualified to bid on the $85.5 million project. The bids were reviewed by the city of Holyoke, members of the School Building Committee, and the consultant team of Mount Vernon Group Architects and Anser Advisory.

Demolition of the former William R. Peck School is now complete, officials said Monday. Thirty-six bricks from the old Peck building have been saved to be used in a future fundraiser organized by school leaders or a parent organization.

“We are grateful for the opportunity to work with Fontaine Bros. in the construction of a new middle school in Holyoke. As the demolition work was underway, it was heartwarming to listen to the tales shared by former students and staff of Peck School,” Mayor Joshua A. Garcia said in a statement.

Construction of the 105,000-square-foot building is expected to last 18 months, with an opening planned for the fall of 2025.

The middle school design is a two-story building with a courtyard in the center. The design was picked from Massachusetts School Building Authority models and has been used three times, mostly recently for Goodnow Brothers Elementary School in Marlborough.

MSBA payments are expected to total $57.6 million, according to the owner’s project manager, leaving Holyoke to pay an estimated $27 million, or 32% of the total cost.

Avoiding a tax override, the city’s financing plan consists of long-term bonds and federal funds from the American Rescue Plan Act and Elementary and Secondary School Emergency Relief Fund.

Fontaine Bros., founded in 1933, has built numerous schools in the Pioneer Valley, including Mountain View School in Easthampton, East Meadow School in Granby, Coburn Elementary School in West Springfield, and the Gilder Science Center at Northfield Mount Hermon School in Gill.