A shortage of sites is the biggest barrier to resolving Northern Ireland's housing problems, it has been claimed.
Even though more than 10,000 social and affordable homes have been built in four years, 22,000 people are still in housing stress.
Cameron Watt, chief executive of the Northern Ireland Federation of Housing Associations, said land supply was a major issue.
He said: "Land supply is the big barrier now to getting much needed homes built.
"We need continued investment from government but we need a game-changer in land supply to ensure that we can continue to deliver much needed homes for people in Belfast and across Northern Ireland."
A total 10,066 social and affordable homes have been built since 2011.
The figure, which represents a £900 million investment, exceeds the Department of Social Development's (DSD) pledge to build 8,000 new homes by 2015.
A further 1,950 will be available by next March.
DSD Minister Mervyn Storey said delivering social housing was a priority.
Speaking from the site of a former fortified police station in north Belfast where new family homes are being built, the minister said: "It is not just about the figures. This is about ensuring that we deliver good, quality homes for people to live in.
"Not only has this investment delivered 10,066 homes but it has helped support the construction industry and provided employment for many people through a difficult economic climate."
North and west Belfast have some of the highest levels of housing deprivation.
Mr Watt added: "Often in these difficult inner city brown field sites, private commercial developers aren't interested.
"It's housing associations working with the Housing Executive and DSD that are able to match public and private investment to bring these sites back into productive use and re-generate areas and provide homes in areas of high social need."