I had new plumbing for a 3 tub sink, etc. at my store. When the inspector
came he told the plumber that he had to add a vent between the sink drain
and the new drain line. Well he added the vent, which opens into the back
room where the sinks are. I didn't think anything about it at the time, but
shouldn't the vent go out the roof or something?
Every once in a while we will get a smell like sewer gas in the back room.
Usually it goes away if I dump some bleach or something down the sink. I
don't know if just running a bunch of water down the sink does the same
thing, I just thought of this. The washrooms where I used to work would
smell like this sometimes, and someone told me it was because the trap in
the floor drain was dry and you just had to pour some water down the drain.
Most vents do go out but there is a vent that opens only when the water is
running. I don't know about your codes, some places allow them, some don't.
Going up through the roof probably would have cost you hundreds of dollars
more for the job. May have even been impossible, depending construction and
Thanks. There is no fixture like this on the end of the pipe. It is just a
2" pvc pipe coming out of the floor. We are doing some remodeling, so I will
ask the guy who does the plumbing to look at this for me.
That is wrong. You want to probably put a "studor" vent on that. I had
a plumber that left the vent off at my place as well. My wife kept
getting sick too. Put a studor on that asap. Make the plumber do it.
I know it can't pass code like that and I question te quality of a
plumber that would leave it like that.
"Then said I, Wisdom [is] better than strength: nevertheless the poor
AKA. an Air Admittance Valve. They are allowed under one plumbing code but
not the other (IRC, UPC) You need that or a direct vent outside or to the
existing vent stack. www.oatey.com lookup AAV
The purpose of a vent is not to allow sever gasses to get outside (though
they will occupy the pipe). The purpose is to prevent a vacuum from sucking
the trap dry when water is drained on that branch or to prevent a pressure
bubble at another fixture from erupting as a gieser.
We can only guess what the plumber did, but it sounds like he failed to
put the breaker on it. You can't legally or properly vent to just an open
pipe into a living space, it must be vented outside or one of the mechanical
vents as I indicated above or dnoyeB indicated. You plumber either did an
improper job or just failed to finish it.
The reason sinks have traps is to prevent sewer gas from getting into
your house. If the trap runs dry, you will get that sewer smell.
However, usually there is no trap on the vent pipe (shouldn't be one
anyway). So, if the vent pipe isn't vented to the outside, you will
get sewer gases inside. Extend the vent pipe at least to the attic
space, but, better yet, to the outside.
I'm no plumber, but it sounds scary to vent sewer gasses into the
You might not smell them, but there are other hazards of sewer gasses
beyond the smell.
YEAH! like a neighbor bozo dumps gasoline down his sewer, vapors might
end up in your attic, sewer gas can contain methane, thats raw natural
never vent into a interior space
Time to call the Mythbusters. For the mosrt part, methane vapors would be
either too dense or not dense enough to ignite but there would be a sweet
spot inbetween where it could be possible. The risks to sewer gas are
mainly health and comfort. I can't remember even one sewer gas explosion
making it to the news in my recent memory.
The floor drain should be vented ( if that's what's there) the best fix if
possible would be to tie the sink vent into the drain vent. The tie must be
a minimum 6" above the flood rim of the sink ( were the water pours out of
the sink onto the floor) It sounds like you had not quiet up to code job
done. If a floor drain water evaporates out of the trap you no longer have a
seal from sewer gas. There are fixes for this called Trap Primers but this
might be beyond your plumbers skill level.
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.