National Trust ACT spokesman Eric Martin said he had understood the government was still considering a new "house museum" in the precinct to showcase the capital's recent architecture, and only read in The Canberra Times on Wednesday that this was not the case.

The ACT government denied it had committed to the plan, describing it as "an idea floated early on in our discussions on the renewal of the Northbourne corridor", while the ACT Heritage Council said it was unaware a site had ever been selected.

In June 2015, during a row over plans to demolish the Northbourne Avenue public housing buildings for private ones, Chief Minister Andrew Barr said it was "envisaged that the ground floor of the Lyneham Tower will be converted to a heritage museum in the future."

Mr Martin, a supporter of a new museum at the heritage-listed units built in the post-war international modernist-style, said it was unfortunate the government had walked away from the idea and that it should have sought feedback before making the decision.

"I'm not aware it's been widely promoting this decision would be taken, and I'm not aware that public comment was able to be provided," he said.

"It's really unfortunate when a number of people are aware of it, and then when it's removed quietly, people come to be aware of it by default.

"It's an opportunity now being lost to provide another incentive to attract visitors to Canberra and promote heritage in its widest sense."

The units would not only have hosted a public housing museum, but a "house museum" showcasing the city's more recent architecture, particularly from the 1960s.

"There's a lot of great architecture and great innovation in that period, and the public as a whole haven't been made aware of that," he said.

Similarly to old hotel buildings in Canberra, the flats could have been re-purposed to attract visitors, Mr Martin said.

"With some creative approach, it could be another element to promote Canberra."

An ACT government spokesman said it had analysed the proposal since it was raised, and found it was not feasible.

It had made other efforts to document the heritage of the area, engaging a photographer for a documentary project on tenants who lived in the dwellings, he said.

The government would adhere to a Heritage Council decision on the precinct by making purchasers of the Northbourne sites preserve certain building types, potentially through "clever adaptive reuse", the spokesman said.

ACT Heritage Council chairman David Flannery said he was not aware the government had ever committed to a museum or selected a site.

While he supported the idea, he said it was only an "aspirational hope" in "early discussions".

"It would cost a fair bit of money to establish such a museum, it would be a significant ongoing cost," he said.

A government brief prepared for Arts Minister Gordon Ramsay in late 2016, released under freedom of information laws, said it should advance plans to open heritage-listed units of the run-down Dickson and Lyneham public housing precinct.

"The presentation of one or more units would assist in demonstrating the government's commitment to the heritage significance of the precinct at a time when the area is undergoing major redevelopment in association with the light rail project," it said.

However the government said on Tuesday it was not "actively considering" creating the museum.

While ACT government estimates for the museum's capital cost were redacted from the briefing documents, it predicted early recurring spending could reach up to $250,000 annually.

Correction: A previous version of this article said the ACT government planned to establish a museum at the Northbourne Flats, not the public housing precinct at Dickson and Lyneham.