Four out of five victims of domestic violence desperate for help were turned away from a crisis refuge last year because it was full.
Sonas Housing revealed almost 600 vulnerable woman living with abuse made contact in 2011, but only 130 women with 250 children could be taken in.
Anne McKeon, chair of Sonas Housing Association, said the lives of women and children are at risk by the lack of support nationwide.
"There is a real need for more domestic violence spaces in the community to alleviate this risk," she said.
Demand for Sonas almost doubled since 2010, the organisation revealed.
Almost 850 women made contact in 2011, including 250 who needed long-term housing or outreach support, but on 550 occasions women were turned away. Approximately 70% had children.
Its annual report revealed December and June were the quietest months for demand, but were followed by massive spikes in February and July which were the busiest.
Ms McKeon said the trends in demand are often family related.
"In December, mothers are aware that children want to spend Christmas in their homes," she continued.
"Younger children may worry that Santa may not be able to find them if they move into a refuge."