Pecan Valley Plumbing
Get help with Sewer Smell in the House
Call Pecan Valley Plumbing, have us call you, or describe the issue.
Prefer to talk?
Call (512) 555-0147A persistent sewer smell indoors, traced to a dry trap, a failed seal, a vent problem or a cracked line rather than just aired out.
01Sewer smell
Each of these narrows down whether the cause is close by or further into the system.
Pointing to something local rather than the whole system: a dried-out trap under a rarely used sink or floor drain, or a seal around a toilet's base that's failed.
Wind direction affecting a poorly placed or undersized vent is one possible cause, alongside a vent that's partly blocked, which can let sewer gas back down into the house instead of venting up and away.
Nearby work, a new fixture, or ground settling can crack a joint or dislodge a seal that had been fine for years, and a smell that keeps strengthening usually means the source isn't drying out on its own.
02In the meantime
None of this fixes it. Both of these limit exposure until the cause is confirmed.
Opening a window and leaving a room where the odor is strong for a while limits how much of it gets breathed in while the source is being tracked down.
Sewer gas can include flammable components, so a strong or worsening smell is a reason to avoid lighting anything nearby and to keep other ignition sources away until the source is found.
Sewer Smell in the House
Serving Round Rock, TX.
03Simple fix or not
A dry trap is the easiest cause to rule out, so it's usually the first thing to check.
Running water for a minute in a sink, tub or floor drain that hasn't been used in a while often clears the smell completely, which points straight to a simple dry trap as the cause.
A smell that persists after every trap in the building has been refilled points beyond a dry trap to a failed seal, a vent problem or a cracked line, and finding which one it is takes an actual look.
04Possible causes
Once a dry trap is ruled out, it's usually one of these.
The most common and easiest cause to fix: a fixture that goes long stretches unused loses the small amount of water that normally blocks gas from the room above it.
The wax ring under a toilet, or the seal around another fixture's drain connection, can dry out, crack or shift enough to let gas past it even though the fixture itself still drains normally.
The pipe that lets sewer gas rise up and out through the roof instead of into the house can be blocked, undersized, or poorly placed relative to nearby walls and rooflines, letting gas find another way in.
A line hidden inside a wall or under a floor doesn't have to be leaking water to leak gas. A crack too small to show as a stain can still be wide enough for sewer gas to pass through it.
05Why it happens
A plumbing system is built to carry sewer gas away from living space, not just wastewater. A trap under every fixture holds a small amount of water that blocks gas from coming back up through the drain, and a vent system lets that gas rise up and out through the roof instead of pressurizing the pipes indoors. A persistent smell means one part of that system, somewhere, has stopped doing its job.
06Questions
Yes. The curved section of pipe under a sink, tub or floor drain holds a small amount of water that seals sewer gas out of the room. A fixture that isn't used for a while can dry out, and once it does, that seal is gone until water runs through it again.
Then the source is probably beyond a dry trap: a failed seal around a toilet or fixture, a vent that isn't drawing air the way it should, or a crack in a drain or vent line somewhere in the building. Finding which one it is takes a look at the fixtures and the accessible piping, not another guess.
It's worth taking seriously rather than just covering it up. Sewer gas can include compounds that are unpleasant or harmful to breathe in quantity, and some are flammable, so a smell that's strong or getting stronger is a reason to increase airflow and have the source found.
Water that cannot be stopped, sewage coming up, no water at all, or a smell of gas: urgent. A drip, a slow drain or a running toilet: worth fixing soon, but not tonight. When in doubt, shut off the water to the fixture and ask.
Pecan Valley Plumbing
Call Pecan Valley Plumbing, have us call you, or describe the issue.
Prefer to talk?
Call (512) 555-0147