Tasmania's housing crisis is putting pressure on the state's overcrowded prison system as inmates struggle to secure a fixed address needed when applying for bail or parole.

Key points: Bethlehem House is one of the only places homeless prisoners can be released to in Hobart

Bethlehem House is one of the only places homeless prisoners can be released to in Hobart It currently has nine remand prisoners on its waiting list

It currently has nine remand prisoners on its waiting list The Government says it recently introduced a new rehousing program

Prisoner advocates say the courts are "criminalising homelessness" because renting or buying is near impossible for parolees and offenders charged with a crime — not in the least because the state is facing a rental crisis.

Men's shelter Bethlehem House is one of the only places prisoners can be released to in Hobart.

It receives government funding for 12 beds — but more than 30 people are given shelter there each night.

"People phone us who are desperate who want to be able to come here," CEO Stephanie Kirkman Meikle said.

"If they can't give Bethlehem House as a suitable bail address, they don't have an opportunity to leave on bail."

She said nine people — currently on remand — are on the wait list to provide Bethlehem House's address on their bail application.

'Warehousing people'

Tasmanian Prisoners Legal Service chair Greg Barns said remand had become a go-to for the courts, instead of an option of last resort.

Stephanie Kirkman Meikle says Bethlehem House has nine people on remand waiting to get into the facility. ( ABC News: Jessica Hayes )

"The reason they are on remand is because in many cases they are ineligible for bail because they don't have a fixed address," he said.

"Effectively through no fault of their own because they're homeless, they find themselves being deprived of their liberty and are having to wait in prison for their case to be heard.

"I think the courts need to be looking closely at this issue of whether or not it's essential in this day and age, taking into account the social circumstances of Tasmania, that a person has a fixed address so that they can get bail."

The state's prison population currently sits at 689 inmates, up from 596 in June last year.

Mr Barns said the high number of people being held in remand was adding to overcrowding issues, with some inmates incarcerated without sentence for as long as two years.

"One of the difficulties with people being on remand is that you don't have access to programs, so if you've got drug addiction issues, you don't get any access to programs, you get nothing really until you are sentenced," he said.

"You're just warehousing people, in very difficult conditions at the moment, where they are subject to continual lockdowns."

'Powder keg about to explode'

There are more than 90 prisoners in Risdon than at this time last year. ( ABC News: Jack Tegg )

Government documents, seen by the ABC, show staff shortages at Risdon Prison have resulted in full or partial lockdowns across large parts of Tasmania's prison network on a daily basis.

A prison employee, who wished to remain anonymous, said the lack of staff was reaching crisis point and was impacting on inmate and staff welfare.

"In maximum security, [prisoners] can be locked up for several days, and in solitary confinement it can be even longer," the source said.

"I don't think we've had a full unlock since before Christmas.

"It's a powder keg about to explode, I don't know how it hasn't already happened."

The source said it was not uncommon for staff to work for up to three weeks straight due to a lack of employees to fill rosters.

The State Government said in a statement the Risdon lockdowns "may be for a very short time in one unit of one prison affecting a very small number of prisoners", or it "may be the whole of the … facility for an extended period".

"Every prisoner gets at least an hour per day of recreation, except due to unforeseen operational circumstances."

The Government said it recently introduced a rehousing program for high and complex-needs prisoners who are exiting prison, and also plans to work with Bethlehem House to develop a new facility.