Rutgers University president Robert L. Barchi on Friday estimated the cost of integrating part of the University of Medicine and Dentistry of New Jersey into the Rutgers system at $50 million to $70 million.

Barchi's latest estimate came after a board of governors meeting Friday, when reporters questioned a perceived increase in cost. Recent estimates have risen up to 50 percent higher than figures cited when the Legislature voted on the merger in June.

Barchi said the initial estimates were for a smaller integration proposal that did not include Newark-based schools such as the New Jersey Dental School, New Jersey Medical School, School of Health Related Professions, School of Nursing, and New Jersey Medical School University Hospital Cancer Center.

"We're talking about a totally different animal now," Barchi said. "It's not an escalating cost. It was a huge escalation in the job."

The costs are a one-time issue, Barchi said. He hopes to find private sources to help allay the financial hit to the school. But he also threw responsibility to legislators.

"We certainly do expect that the state bears a significant responsibility here," he said. "We certainly don't have those kinds of margins in our operating budget to make this up."

At the meeting, the board unanimously approved renovations of two historic buildings on the Camden campus: $2.5 million to create an alumni house, and $4.5 million to create a writers house.

A combined $6.25 million for the two projects will come from a school fund, with the remaining $750,000 expected from gifts and donations.

The writers house will be in the Henry Genet Taylor House at 305 Cooper St., which was built in 1885 and added to the National Register of Historic Places in 1971. When complete, the facility will provide a space for the school's English and creative writing programs.

The alumni house will be at 312 Cooper and house the alumni and development offices. The project also includes the addition of an elevator to the building, which once housed the American Red Cross of Camden County.

Both projects will begin next summer; the expected completion dates are July 2015 for the writers house and April 2014 for the alumni house.