Amid sustained concerns about detainee welfare, Western Australia's government will pump an extra $25 million into the state's only juvenile prison.
A new crisis care unit will provide vulnerable detainees with a "safe and therapeutic" environment, Corrective Services Minister Bill Johnston says.
The government is also promising improvements to the facility's intensive supervision unit, including new recreation areas and observation cells, through the investment in next month's budget.
It comes after a senior judge described one teenager's time at Banksia Hill as one of "prolonged systematic dehumanisation and deprivation".
Perth Children's Court in February heard a 15-year-old boy had spent 79 days on remand in the intensive supervision unit.
The stint included 33 days where he was confined to his cell alone with no fresh air or exercise.
The boy was being sentenced by court president Hylton Quail for burglary and a string of assaults on officers at Banksia Hill, all but one of which occurred while he was in the ISU.
Judge Quail said the boy, who suffered from fetal alcohol spectrum disorder and post-traumatic stress disorder after experiencing severe childhood neglect, was "one of the most damaged children to have appeared before me".
He imposed a community release order, describing the boy's time at Banksia Hill as one of "prolonged systematic dehumanisation and deprivation".
"When you treat a damaged child like an animal, they will behave like one, and if you want to make a monster, this is how you do it," he said.
Mr Johnston said the new funding would address immediate and long-term needs.
"I understand Banksia Hill has had its challenges in the past year but the McGowan government remains committed to the safety of both staff and detainees," he said on Monday.
"This extra funding will protect some of our most vulnerable young people and enhance community safety, by ensuring detainees are supported and empowered not to reoffend."
The union representing Banksia Hill employees in February warned staffing levels were regularly below safe standards.
Mr Johnston said at the time 40 new staff were in training to start work in March or April and infrastructure was being improved.
The new package includes funding for an Aboriginal services unit to provide cultural support and services.
A further eight Aboriginal welfare officers and Aboriginal medical and mental health workers will be hired, bringing the total to 12.
