MARBLEHEAD — Marblehead Museum had to substantially increase its budget for the renovation to 157 Washington St. due to unforeseen structural issues.

The property adjacent to the Lee Mansion has been under construction since the museum acquired it in April 2021. Museum Executive Director Lauren McCormack explained that she and the museum’s staff were aware of the fact that the property was also once owned by Jeremiah Lee and used as a kitchen, carriage house, and slave quarters.

Thanks to a donation from Standley Goodwin and the help of Pat Lausier and National Grand Bank, the museum was able to purchase the building. Since then, it has been working on renovating it into a historically accurate exhibit that is slated to open in June 2025.

The unforeseen issues added a total of $200,000 to the project’s $1 million budget.

“There were some major structural issues,” McCormack said. “They were caused by multiple things including old powderpost beetle damage, deflected beams, beams that had been cut.”

She added that the majority of the work done so far has been accessing the compromised aspects of the structure, and the process of implementing the fixes is now underway. McCormack noted that one major reason these issues exist is the constant changes made to the structure throughout its 250-year existence, including when it was at one point both raised and added onto by 5 feet.

“Sometimes things weren’t done the way we would do them today, which made the structure susceptible to issues,” McCormack said. “So to ensure that this building is around for another 250 years, we’ve had to take some action which is not inexpensive.”

The museum has received more than $600,000 in grants thus far to go toward the completion of the exhibit. It is still fundraising through donations and grant opportunities. McCormack sees no impending delays for the exhibit’s opening despite the additional work needed.

“We’re trying to get this work done and then move on to the rest of the preservation and construction so that we can open,” McCormack explained. “If things keep progressing as they are, we are still on track to open to the public in June of 2025.”