Sewer smell in the house
A sewer smell usually means gas is getting past a seal or trap that should block it. Most causes are simple.
Smell like rotten eggs near a gas appliance? That can be natural gas, not sewer gas. Leave the house and call your gas company or 911.
Check these first
- Unused drains. A guest shower, basement floor drain or utility sink that's rarely used can dry out its trap. Run water for a minute to refill it.
- Toilet base. A failed wax ring under a toilet lets gas escape, sometimes with a little water around the base.
- Bathroom sink overflow. Gunk in the overflow hole can smell. Clean it with a brush and hot water.
- Washer drain. A standpipe without a proper trap, or a dirty washer, can smell like sewage.
When it's a plumber's job
- The smell is strongest near walls or comes and goes with rain or wind, which can point to a cracked pipe or blocked roof vent.
- Several drains are slow or gurgling, a sign of a main line problem.
- You see water stains or wet spots near pipes.
A plumber can run a smoke test or camera inspection to find a hidden leak in the drain or vent system.