Sewage odor or gas is always present in the sewer system and cannot be eliminated. This is why there are provisions in the uniform plumbing code to ensure that vent pipes and traps are installed to the house plumbing systems. Vent pipes on the roof tops allow the sewer system to breath. Traps are installed to retain a small amount of water which acts as a seal to prevent sewer gasses from entering the home.

• Caps on floor traps and cleanouts are not properly installed
• Infrequently used drains no longer have water in the trap
• Cleanout plugs are removed from the inside of floor drains
• Cracked or separated vent pipes in the interior of the structure will allow sewer gas into your house
• Visually check for one of these conditions and correct if needed. If odor problems continue, have your plumber check out the entire house system for any drain system air leaks