Sewage Smell in House? 7 Causes (Some Are Dangerous)
Harmless (but fix them) causes
- Dry P-trap. An unused floor drain, guest shower, or sink lets sewer gas up. Run water for 30 seconds.
- Dirty garbage disposal. Clean the splash guard.
- Biofilm in a drain. Scrub the overflow and stopper.
Causes that need a plumber
- Failed toilet wax ring. Sewer gas escapes at the base. Needs a reset.
- Cracked or blocked vent stack. Gas cannot escape through the roof, so it comes inside.
- Broken sewer line under the slab or in the yard. Often paired with soggy ground, slow drains, or gurgling.
- Sewer backup starting. Smell comes first, sewage second.
Why sewer gas matters
Sewer gas contains hydrogen sulfide and methane. In high concentrations it is a health and fire risk. Persistent smell is never normal.
What we do
A sewer camera inspection shows exactly what is happening in the line. If there is a break, we repair it — often with trenchless sewer repair that avoids digging up your yard.
Need help now? Rick Staley's Plumbing provides 24/7 sewer line repair across Colorado. Call (888) 480-9811 for same-day service.