Only the furnishings and the Flugelman sculpture out the front will remain of the historic residential hall when the site is developed into two new accommodation towers, the university revealed on Wednesday.

Demolition of the existing hall is scheduled for early next year, with more than 800 students to move into the new sister towers from 2019.

ANU vice-chancellor Brian Schmidt said in a statement the new residential blocks would pay "homage" to the old Bruce Hall.

"It is clear there is a great desire to preserve the unique culture and experience of living at Bruce Hall. The iconic furniture and art will be retained, and the dining room and social spaces will remain as focal points to bring people together in a community culture," Professor Schmidt said in a statement.

The announcement confirmed what former residents of the college had long feared.

Plans to demolish the university's oldest undergraduate residential college first emerged in March this year when the vice-chancellor said the university was exploring an opportunity "to design and build a new Bruce Hall", intended to open in 2018.

Professor Schmidt said the feedback received from that consultation had been folded into the final plans for the new halls.

"I think the results of that work are evident in the outstanding designs we now have in place," Professor Schmidt said.

But a former president of Bruce Hall, Andrew Hargrave, described the outcome as a "stitch-up".

"The ANU has engineered this process from the start to get the outcome they wanted," Mr Hargrave said.

"The new façade pays no respect to the existing building. The architects say they think red bricks are a key heritage element to be kept, as if red bricks were unique to Bruce Hall. It's laughable."

However ANU's executive director of administration and planning Chris Grange maintained the plans had been reshaped by conversations with past and present students.

"We've got to balance off alumni perspectives and historical perspectives with what our current students are saying. I'm not going to step away from the fact we've spent a lot of time listening to what current residents and what current students of the ANU think this accommodation should be like," Mr Grange said.

"We've rethought the dining room extensively and some of the alumni who've seen different versions of that have acknowledged how much it's improved over that six-month period. We've also changed the number of rooms in the proposed new Bruce Hall, we're reducing the number of rooms to address some of the feedback we've got."

The university also hit back at criticism of its decision not to tender out the design work.

NettletonTribe, the company that designed the uni's last few accommodation projects including SA5, was handed the design contract for the twin accommodation towers, a choice Mr Grange defended.

"There's a team of people both inside the ANU and a team of consultants who have a really long track record of building student accommodation on the ANU and that track record, that experience, is worth a lot to the ANU in terms of understanding what students need and what has worked and what doesn't work," Mr Grange said.

"Ultimately the builder will get most of the $100 million and the builder is out to tender at the moment."

Meanwhile former ANU architect Derek Wrigley, who helped to design the existing Bruce Hall, said he was shocked and saddened by the decision to tear it down.

He said it was pointless to demolish the historic dining hall to open University Avenue up to Clunies Ross Street, in line with the Griffins' original vision for Canberra, given a CSIRO building blocks the axis.

"If you look at the War Memorial, if you look at the Australian Memorial or you look at Parliament House you see terminal buildings at the end of each axis. If you imagine yourself looking down the University Avenue axis all you'll see will be CSIRO buildings, which is appallingly bad, quite frankly," Mr Wrigley said.

Professor Schmidt said the Bruce Hall "culture and tradition" would be kept alive while its residents were moved to another accommodation block by sending Bruce furniture and artefacts with them. This include's the college's mascot, the Uroboros, Chris Grange confirmed.

But heritage spokesman for the National Trust Eric Martin said the building had unassessed heritage value.

"The finishings and the Flugelman Sculpture are some of the heritage values but the building has other heritage values and how they may either be integrated with or affected by the development have not been adequately addressed," Mr Martin said.