Housing Executive homes in Northern Ireland need £1 billion worth of work done to them soon, Nelson McCausland said.
The Social Development Minister wants some of the money to be raised through borrowing by housing associations as he dismantles the 40-year-old Executive.
Mr McCausland said planned restructuring afforded the opportunity to build more houses and improve quality.
"Some of the Housing Executive stock, the older properties, need a tremendous amount of work done to them," he said.
"We are talking about a billion pounds of work in the short term to get that stock, all of it, up to the standard that we should be able to expect and that tenants should be able to expect."
Over 30 years the works bill could be £5-6 billion.
Mr McCausland said that sort of money was not currently available to the public sector.
"But if we move the stock over eventually to effectively the housing association sector it enables them to borrow money so therefore the work can be funded," he told the assembly.
Mr McCausland is proposing major reforms, including a new regional housing body.
The Housing Executive is one of Northern Ireland's largest public bodies, with almost 3,000 staff and 90,000 homes. It provides social housing let at low rents and on a secure basis to people on low incomes and benefits but has faced controversy over the handling of maintenance contracts and underwent extensive change at the top of the organisation.