Dublin City Council has set up a dedicated unit to target rogue landlords who leave tenants in slum conditions.
Residents are being urged to report problems like overcrowding, fire hazards, damp and rats.
It follows a Prime Time programme last year which exposed three residential properties that were housing 120 tenants between them.
Chair of Dublin City Council's housing committee, Daithi Doolan, welcomes the move but says the local authority needs more power.
He said: "I must also appeal to the Government to give us robust legislation so we can take landlords to court.
"What is missing in all this is that we don't have enough power to make the landlords pay the costs we think they should be paying to upgrade the houses.
- Digital Desk