Step 4 · Inspect and Clear the Plumbing Vent Stack

This is the step most people slow down on. Take it one move at a time — there’s no rush, and you can rewind the clip as many times as you need.

If clearing the local drain doesn't solve the problem, the issue is almost certainly a blocked plumbing vent. This vent pipe, which exits through your roof, allows air to enter the system and equalize pressure. When blocked, draining water creates a vacuum, causing the gurgle. Using a sturdy ladder and proper safety precautions (like a safety harness), access your roof. Locate the plumbing vent stack, usually a 1.5 to 3-inch PVC or cast iron pipe. Look into the vent opening with a flashlight for obvious blockages like leaves, animal nests, or debris. Use the garden hose to spray a high-pressure jet of water down the vent to clear it. If the clog is stubborn, you may need to feed the drain snake down the vent to break it up. Have a helper inside listen for water flowing freely in the pipes.