08/06/2026
The smell most people notice is usually hydrogen sulfide, which has a strong rotten egg or sulfur-like odor. Even small amounts can be very noticeable, especially indoors.
Your plumbing system is designed to keep these gases out of your living space. It does this through:
π¨βπ§ P-traps, which hold water and block gases from coming up through drains
π¨βπ§ Vent pipes, which move sewer gases safely outside through the roof
π¨βπ§ Sealed pipe connections, which keep wastewater and gases contained
π¨βπ§ Cleanouts and drain covers, which help maintain pressure and access points
π¨βπ§ Proper sewer or septic connections, which carry waste away from the home
When one part of that system fails, dries out, cracks, clogs, or loses its seal, sewer gas can enter the house.