A new apartment building to house the homeless, or people at risk of becoming homeless, will open in downtown Calgary next fall.

The 74-unit building will go up at the corner of Fifth Avenue and Ninth Street S.W., land that was sold to charitable real estate developer HomeSpace at a $3.8-million discount by the city.

The federal government committed $9.77 million to the project.

"This build will be our largest affordable housing development to date," said HomeSpace CEO Bernadette Majdell in an emailed release.

Sixteen of the units in the building will be accessible, and all units will be rented at 65 per cent of the median market rent in the neighbourhood or less.

The land was one of six sold by the city to non-profits at below-market values for new affordable housing projects last year.

David Bissett, a local philanthropist who made a significant contribution to the project along with his wife, Leslie, said he wanted to give back to a community that has supported him.

"You know, I can't take it with me," Bissett said. "It feels really good."