During a recent service visit in Carlisle, MA, a homeowner asked our technician to look at a showerhead spraying water out of its side — but the conversation that followed uncovered a much more common household mystery: an intermittent odor in the basement that nobody could quite trace.
The Original Complaint: A Showerhead Spraying Sideways
The service call started simple. One of the home's showerheads was shooting water out of the side instead of down, so the homeowners had stopped using it entirely and covered it with a washcloth in the meantime. When the Jeneral Plumbing technician took the showerhead apart, the cause was clear: the rubber gasket inside had been pinched and had spun out of place, most likely from someone over-tightening the showerhead by hand in an attempt to stop the spraying.
The technician was able to reposition the gasket and reassemble the showerhead without needing a replacement part. That said, it's worth noting that because the gasket had already been compressed, there's a chance it could shift again if the showerhead is handled roughly in the future. If that happens, the fix is either a new showerhead or disassembling it again to reset the gasket — a quick, low-cost repair either way, though not necessarily a permanent one if the gasket continues to be stressed.
The Bigger Question: Where Is That Basement Smell Coming From?
While downstairs, the homeowner mentioned an odor that came and went in the basement — sometimes noticeable, sometimes not. The basement had its own shower that was almost never used, which is an important clue.
Every drain fixture in a home — showers, sinks, toilets — has a P-trap, the curved section of pipe that holds a small amount of standing water. That water seal is what blocks sewer gas from rising up through the pipes and into your living space. When a fixture sits unused for weeks at a time, the water in that trap can slowly evaporate. Once the trap runs dry, there's nothing stopping sewer gas from migrating into the room.
This matches the pattern described at the Carlisle home: an odor that showed up intermittently, near a basement shower that was rarely, if ever, run.
The Fix Is Simple — But Easy to Forget
For any drain that isn't used regularly, running water down it for about two minutes once a month is enough to refill the trap and maintain the seal. It's a small habit, but it directly prevents sewer gas odors from entering the home through unused fixtures.
In this case, the home also had a water softener installed, which the technician noted should already be addressing any odor that might otherwise come through the water supply itself. That made a dry drain trap the more likely explanation for the smell rather than a water quality issue.
When an Odor Might Be Something Else
Not every basement smell traces back to a dry trap. The homeowner also mentioned uncleaned HVAC vents and the presence of pets as possible contributors, and those are reasonable things to rule out separately — duct cleaning is outside the scope of plumbing work. But if an odor keeps returning after you've refilled every infrequently used trap in the house, that's a sign it's worth having a licensed plumber take a closer look, since it could point to a drain line issue rather than a simple evaporation problem.
When to Call a Professional
Sewer gas exposure is a real health and safety concern, not just a nuisance smell — persistent odors that don't resolve with regular trap maintenance should be evaluated by a professional rather than guessed at. A licensed plumber can confirm whether a trap is dry, check for a cracked or improperly vented drain line, and rule out other causes before you spend money on unrelated remediation like duct cleaning.
If you're dealing with a drain or fixture issue — minor or otherwise — the team at Jeneral Plumbing's drain repair services can diagnose the source rather than leave you guessing. For homes with recurring odor or drainage concerns, a service plan can also help keep fixtures and traps checked on a regular basis before small issues turn into bigger ones.
Call Jeneral Plumbing
Whether it's a leaking showerhead, a mysterious odor, or something else entirely, Jeneral Plumbing is here to help homeowners in Carlisle and the surrounding area figure out what's really going on — not just sell a repair. Regular-hours visits include an $80 dispatch fee — the cost of the visit, waived when you hire us for the work. Call us at (978) 392-7789 to schedule a visit.
This post is for informational purposes only and is not a substitute for an in-person evaluation by a licensed plumbing professional.
Written by Sierra Sorongon.
This article was drafted with AI writing tools and edited before publication. AI tools did not inspect any job or validate technical conclusions.
Last updated .