90 per cent of homes in Rent Pressure Zones across the country have failed to meet minimum housing standards.
Figures supplied to The Sunday Business Post by local authorities with RPZs show that 16,441 private rental properties were inspected last year.
Those figures show there's been a significant increase in the number of private rental homes being inspected by local councils, with 58% more homes investigated in 2018 than the previous year.
The worst offenders were rental homes in Limerick, Galway and Louth.
None of the private rentals inspected passed the minimum housing standards.
County Wicklow homes fared the best, of 588 homes to come under scrutiny, 56% met the standards.
Dublin City Council inspected the most properties, 3,561, of which more than 95% failed.
Minimum standards landlords to meet requirements such as structural repair, sanitation, heating, light, safety of gas and electrical supplies and absence of damp and rot.
