Thousands of tenants saw their homes improved after sub-standard living conditions were uncovered in a five-year inspections scheme.
Overcrowding, mould, faulty electrics and fire safety failings were found during visits to homes in Harehills and Beeston.
Leeds City Council said almost 3,000 legal notices were issued after private landlords were required to sign up to a selective licensing scheme.
Launched in 2020, the project covered around 6,500 homes in the two communities, which are among the city’s poorest.
Squalid conditions in some homes were described in a report to the council’s Environment, Housing and Communities scrutiny board.
Rotting floors, crumbling plaster, bare wiring and a dangerous staircase was found in a Harehills flat which had no smoke alarms.
The report said: “There was also insufficient space for living, cooking and sleeping.”
The tenant, who was suffering with kidney failure, was found a better home by the council’s homelessness service.
A scrutiny board meeting on Thursday was told selective licensing could be launched in other parts of the city.
Labour Cllr Luke Farley, who represents Burmantofts and Richmond Hill, said: “It’s absolutely appalling when you see the state of housing some people in this city are having to live in.
“You wouldn’t keep a dog in some of these properties. It’s absolutely vile.”
The report said more than 400 civil penalty notices and 2,900 legal notices were issued during the scheme.
In another property, two brothers were living with a broken window, damp, mould and water leaks.
The report said: “One was a full time carer for his brother, leaving him isolated and with poor mental health.”
They were among hundreds of people referred for mental health support and help claiming benefits.
Arrests were made after officers found some homes were being used for criminality.
More than 500 cannabis farms were found, along with brothels and properties used for “cuckooing”, where criminals exploit the homes of vulnerable people.
The report said 1,430 properties were improved due to hazards being removed and 6,023 people benefited from better quality homes.
Labour’s Jess Lennox, executive member for housing, said the scheme was not designed to penalise landlords.
She said: “Private renting is a massive part of our housing market in Leeds.”
But she added: “We mustn’t expect people to live in sub-standard accommodation. This is about making our city a safe and healthy place for people to live.”
The Harehills and Beeston scheme ended on 5 January, the maximum period allowed under housing legislation.
It means extra powers under the Housing Act are no longer available to the council.
The report said some enforcement investigations started before the end of the scheme were ongoing.
