Assess the problem Track down the impacted drain and extent of backup Check out if a number of drains are impacted (implies key line situation) Seek out visible drinking water injury or overflow Basic Do-it-yourself Steps Pour boiling drinking water down drain Use plunger suitable for sink/toilet Test baking soda https://www.kawatan.net/why-you-should-never-use-baking-soda-and-vinegar-to-unclog-a-drain/