A generous gift from an Ontario religious order will cover more than half the remaining cost of a permanent home for dozens of homeless women.

The Grey Sisters of the Immaculate Conception, a Roman Catholic group based in Pembroke, Ont., have donated $1 million toward a new supportive housing facility being built on Ottawa's Booth Street.

The announcement was made Thursday by Cornerstone, the group that is building and operating the home for 42 vulnerable women, including 20 seniors.

Although the fundraising campaign officially launched just Thursday morning, $1.4 million has already been pledged or donated, including the amount from the Grey Sisters.

That is an "incredible" gift that provides a strong boost, said Sue Garvey, director of Cornerstone, at a news conference.

She estimated that about 1000 women become homeless in Ottawa every year, and 10 to 15 are turned away from Cornerstone's emergency shelter each night.

"The lack of affordable housing for women in Ottawa is desperate," she said, adding that makes it difficult for the women to overcome other problems.

"Once they have that affordable housing, they'll be able to move on in their lives."

The new four-storey building, located across the street from the Somerset West Community Health Centre, will include individual studio apartments, common areas, and offices for staff who offer support services to the residents. Construction will begin at the end of March, and the building is scheduled to open in April 2011.

The federal, provincial and municipal governments have made contributions worth more than $9 million toward the $11.5 million project. Cornerstone hopes to raise the remaining $600,000 for the new building over the next three years.

The work of the Grey Sisters, founded in 1926, focuses on social and ecological justice. Garvey said they have been encouraging Cornerstone's work on the supportive housing project for the past five years. Pembroke is about 150 kilometres west of Ottawa.