The federal government’s $2.9 billion program to develop 40,000 social and affordable homes over the next five years has a 12-month window to buy unsold apartment stock before the private market recovers, Housing Australia head Nathan Dal Bon says.

The first tender that started on Monday – subsidised by an annual $500 million from the Housing Australia Future Fund and $70 million from the federal government’s National Housing Accord Facility – could see bids from developers, states and other qualifying groups using the next year to make so-called spot purchases of unsold homes, Mr Dal Bon said.