Sheffield council claims it receives 2,000 complaints relating to private rental sector conditions each year - and in one month it says it has secured a record number of convictions.
During November, the authority took seven landlords to court for offences relating to disrepair, safety measures, failing to meet legal requirements, harassment or illegal eviction.
All seven pleaded guilty or were found guilty, with the largest fine and court costs awarded at £29,220.
Every year the council responds to around 2,000 complaints about private housing, with most relating to safety, damp and cold.
In the last six months the authority has prosecuted nine landlords and says it has more court cases pending for early in the New Year.
“We had a particularly busy time in November and prosecuted some landlords that engaged in really bad practices” claims a council spokeswoman.
“Everyone has the right to live in safe housing and be treated in a respectful, lawful way, but sadly that’s not always the case. We see people who have been badly treated, put at risk or exploited, and we will do whatever we can to clamp down on this” she adds.