Opposition to the redevelopment of one of Sydney’s most controversial harbourside apartment blocks has ramped up as unions move to block work on the site.

The CFMEU construction union has placed an interim Green Ban on the Sirius building at The Rocks, meaning no unionised workforce is allowed to work on the building that overlooks the Harbour Bridge and Opera House.

The building, which has been used for social housing since it opened more than 30 years ago, has been slated for redevelopment into hundreds of private apartments by the NSW government.

"It is one of the last areas of public housing remaining in the district," CFMEU NSW Secretary Brian Parker said.

"The top end of town moves in and ordinary working people are locked out of the suburbs they have called home for more than a century."

The move comes as the Save Our Sirius campaign hit the $35,000 milestone in its crowd fund raising campaign to take the government to court over its decision to refuse heritage building status for the building.

The NSW government has rejected a heritage listing for the apartments - built in a Brutalist architectural style - because it would slash tens of millions of dollars from the site's sale price.

"I am not listing it because whatever its heritage value, even at its highest that value is greatly outweighed by what would be a huge loss of extra funds from the sale of the site," NSW Environment Minister Mark Speakman said in late July.

The sale funds would be used to build social housing elsewhere, he said.

  • That's a dreadful way to think about heritage value. A building should be listed or otherwise as heritage based upon whether or not it has genuine heritage value. The impact upon price should have no bearing on this decision whatsoever and should be considered to be totally irrelevant.

    That said, the union's actions are likewise out of order. Irrespective of understandable social concerns, the licence of a union is to represent the views of its members on matters pertaining to workplace relations. The CFMEU's members have not given the union licence to speak on their behalf with regard to any matter outside of the workplace relations matters about which members have given the union authority to represent them. They should remember the limits of the mandate which they have been given by their members and stick to that.

  • No unionised workforce FANTASTIC that means that the project will cost 25 to 30% less to redevelop. It`s a magnanimous gesture of the CFMEU to finally put some money back into the economy.