Stop sewer gas from entering the home by cleaning the roof vents. The process requires climbing on the roof and putting water in the vent with a garden hose. If the water backs up to the top of the vent, use a plumbing snake to clear the blockage.
- Set the ladder up safely
Set up the ladder correctly. The legs should be level and firmly planted. Attach a rope to the bottom rung of the ladder and to the house to prevent it from slipping. Extend the top of the ladder at least 3 feet above the edge of the roof.
- Attempt to fill the vent with water
Locate the vent for the room where the sewer gas smell is strongest. Use a water hose and attempt to fill the vent to the top. If water fills the vent, it is blocked and likely the cause of the smell. If the vent does not fill with water, look for another cause for the sewer gas smell, such as a trap where water is evaporating or a break in the sewer line.
- Use a plumber's snake
If the vent fills, unblock it. Insert the end of a plumber's snake into the vent. Push the snake forward while turning. As the snake advances, it may meet some resistance. Continue turning and applying pressure to clear the blockage. Once the vent is clear, it should drain quickly. Add more water to ensure the material that formed the plug moves through the sewer line.