The Greens and crossbenchers backed the government’s Housing Australia Future Fund in the upper house on Wednesday.

The fund will leverage $10 billion and use the interest to fund 30,000 social and affordable homes over five years.

The minor party signed up to support the fund after the government agreed to set aside an extra $1 billion for the National Housing Infrastructure Facility on top of $2 billion previously promised.

The government has committed to spending a minimum of $500 million on social and affordable housing each year as part of its deal with the Greens.

The coalition remains opposed to the fund, arguing it will be inflationary and fail to address the problem.

Liberal frontbencher Anne Ruston said deals with the Greens had already tacked on billions of extra dollars and questioned where the minimum $500 million would come from if the investment fund made a loss in any given year.

“We have seen a 30 per cent blowout in the cost of this fund,” she said, referring to all the concessions the government gave the Greens.

“This is just another classic example of a rushed headline policy that has not had the detail dealt with.”

Assistant Minister Tim Ayres said the money would come from the fund but noted that investment objectives aren’t always met in any given year, which was why the spending floor for social housing was put in.

Ayres said similar investment funds had provided “consistent and reliable annual disbursements”.

Infrastructure Minister Catherine King said significant planning reforms were needed to unlock the housing investment and every council and every regional economic body had a role in making sure the homes are built.

Housing Minister Julie Collins said the policy was part of a broader suite of measures that would address social and affordable housing, homelessness and home ownership rates.

The Senate’s amendments need to be ticked off by the government-controlled lower house before it can become law.

The Greens say they have not given up on a fight to secure rental caps and freezes, pledging to use it as a bargaining chip in negotiations over future legislation.

Rent freezes have been ruled out by state and territory leaders at national cabinet.

-AAP