The Tisbury select board and school committee took a first step this week toward launching the $55 million renovation and addition project at the town school that voters overwhelmingly backed last month.

Meeting jointly online Tuesday afternoon, the two boards voted unanimously to hire a construction manager at risk, who will guarantee to deliver the project within a stated maximum price. The school building committee had previously recommended this method in a letter to town officials.

While a firm timeline is yet to be established, construction is expected to take about two years, beginning next January.

Issuing a request for proposals and vetting candidates for the construction manager will be the job of Daedalus Projects, the Boston consultants serving as owner’s project manager for the school.

A committee will be appointed to review candidates, school committee chairman Amy Houghton said.

Once a construction manager at risk is chosen, preliminary work will begin on multiple fronts.

The first task is to ensure that temporary school facilities are in place by January, when the 1929 school building on West Spring street will be emptied. A nearby plot of town-owned land on West William street is planned as a temporary school campus.

The construction manager also will begin working with Boston-based project designer Tappé Architects to develop construction documents from the schematic design voters approved last month.

Tuesday’s joint meeting, which adjourned less than 20 minutes after it began, got off to a rough start when town resident Anna Edey began reading a statement that asked the town to stop working with Daedalus and Tappé, claiming that there are environmental shortcomings in the design.

Ms. Houghton told Ms. Edey that while there will be time for more public comment on the design as preliminary work progresses, the agenda for Tuesday’s meeting was limited to deciding on the construction manager.

“There is not going to be any construction management,” Ms. Edey responded, raising her voice.

“Anna, with all due respect, we’ve been working on this for two years,” said school committee vice chairman Mike Watts, who also served on the building committee.

The meeting then continued to brief discussion and voting.

— Louisa Hufstader