Demand for services provided by the Peter McVerry Trust rose by 89% last year, according to the homeless charity.

The NGO’s annual report says 2015 was its busiest year on record as rising numbers of homeless people sought assistance.

The three main issues facing clients, after homelessness, were drug use, family breakdown and mental health.

It comes as new figures from the Department of Environment show there were 6,525 people in emergency accommodation in July, a year-on-year increase of 40%.

Pat Doyle, CEO of Peter McVerry Trust, called on Minister Simon Coveney to take an "aggressive approach" to increasing housing supply across the country.

He said empty units needed to be put back into residential use through a programme of compulsory purchases.

The charity’s report highlights that it organised 3,847 residential placements provided through emergency homeless accommodation services last year.

Some 171 young people were also supported in moving into their own homes – the largest number achieved in a single year, according to the Peter McVerry Trust.

The charity helped a total of 4,705 people, with the average client being 31 years of age. Some 81% had a current or past history of drug misuse.

Its residential community detox service provided support to 78 individuals using methadone or cannabis.

Linking rents to consumer price index

A total of 56 people were given accommodation placements in 2015 through the Peter McVerry Trust's drug free aftercare service.

The organisation also provided 149,000 meals and opened three new emergency accommodation facilities in Dublin, comprising 29 beds and 12 family suites.

It opened Ireland’s first homeless youth café in the capital and launched a new information freephone service in Kildare.

Mr Doyle said the figures underline the need to bring forward legislation to link rents to the consumer price index.

"Unless measures are brought forward to tackle the root cause of accommodation costs and restrain price rises, there will be widespread and long lasting consequences for both the economy and wider society," he said.

Mr Doyle added it was an "affront" to homeless people across the state that so many homes continue to lie empty.

"Local authorities took a very assertive approach to reducing their vacant stock and increased supply at a crucial time. Now, we need to see an aggressive approach to empty private homes," he said.