The former public-housing block will become commercial office space as part of the $30.2 million development which would see 143 units built on the site at the corner of Morphett Street and Northbourne Avenue.

Designed by Stewart Architecture, the buildings would include 22 one-bedroom units, 113 two-bedroom units and eight three-bedroom units, with floor areas between 44.5 and 80 square metres.

Both apartment buildings would have partially covered rooftop terraces and a garden, according to plans submitted on behalf of the developer.

The plans include a new driveway on Morphett Street to allow access to basement car parking at the rear of the site, which would provide 191 car parking spaces and six motorcycle spaces.

Plans also show the proposed driveway near the intersection of Morphett Street and Northbourne Avenue.

Pedestrians would be able to enter foyers at the front of the two apartment buildings from Northbourne Avenue.

The rooftop terraces and gardens would see the height of the building reach above the 25-metre parapet limit set for the Nortbourne Avenue corridor. This is permitted provided structures above the height limit are set back.

A report prepared for the developer by Canberra Town Planning said the block would be subdivided to keep the heritage building separate from the residential development, and residents would have no ongoing commitment to the maintenance of the heritage building.

The plans show that the developer would remove internal walls from the Dickson Towers building and install new, disabled-access-compliant bathrooms before commercial tenants moved in.

The ACT Heritage Council registered the northernmost Dickson Towers building in 2015 as part of a representative sample of the public housing precinct along Northbourne Avenue, found to be a good example of the Bauhaus-inspired post-war international style.

The ACT government originally planned to demolish all the Dickson Towers buildings to make way for a 160-apartment complex on the site.

A heritage assessment report for Art Group's development was written by architecture firm Conrad Gargett Ancher Mortlock Woolley, which emerged from the firm that designed the buildings.

Architects Ancher Mortlock and Murray designed the Northbourne Avenue public housing precinct, which was built between 1959 and 1962.

Mr Roso bought the large Northbourne Avenue site at auction in 2016 for $37 million. It stretches from Morphett Street to the former Canberra visitors centre, which is currently the light-rail project office.

Mr Roso promised a public design competition for the site, which is being advertised as the Soho precinct. The competition never eventuated.

Development approval has been granted for Art Group's Mulberry development, which will see 409 apartments built across six buildings facing Northbourne Avenue at the southern end of the site. Construction is expected to start in the first half of this year.

Mr Roso was contacted for comment.