Evaluate your situation Identify the influenced drain and extent of backup Test if a number of drains are affected (implies principal line issue) Try to look for seen water damage or overflow Fundamental Do it yourself Ways Pour boiling h2o down drain Use plunger suitable for sink/toilet Try out baking https://www.kawatan.net/how-to-find-emergency-drain-cleaning-and-plumber-services-in-etobicoke/