If your landlord doesn’t fix the problem after you have told the landlord about it you can:

• contact your municipality to ask for municipal standards and by-laws regarding your particular issue, or health departments;
• file an application about maintenance (form T6) with the LTB. The LTB will then schedule a hearing where both the landlord and tenant can provide evidence about the problem.

If you already have received an order from the LTB to fix the problem and your landlord is not following the order, you can contact the Rental Housing Enforcement Unit.

Source: www.sjto.gov.on.ca