Let's play "What's That Smell?"! (Sewer gas?)

General Questions
#1

There’s a smell in our bedroom. It is a Very Bad Smell. Kind of damp, kind of dank, maybe a little rotten eggy. It came on very suddenly yesterday.

Thinking it might be sewer gas, I investigated the very rarely used half bath attached to the bedroom. Now, the bathroom itself doesn’t really smell. But since we couldn’t come up with anything else it could be, I tried running a bunch of water down the sink. Didn’t help. I tried duct taping over the sink drain and closing the door and sort of stuffing a towel under it. That helped (but did not entirely fix the problem) - at any rate, it smelled a lot better when we came home from dinner last night.

This morning I had my husband untape the drain and run a bunch of hot water through it. (I started thinking, hey, this stuff might not be that great for a pregnant lady to breathe.) The smell has returned.

My understanding, albeit limited, is that water should have fixed it if the problem was that the trap on the sink dried out, right? Is that not correct? Does that mean it ISN’T the sink? (Remember, the smell isn’t specifically coming from anywhere special and is not particularly bad in the bathroom.) Ideas?

ETA - for clarity, the reason I thought it was probably the sink is that the toilet gets used sometimes but the sink never does.

#2

another source is the toilet. there is water in the bowl and trap (internal to the toilet to block gas) but the wax seal under the toilet may be letting gas through.

#3

You might want to borrow a gas tester from some utility worker - the kind that checks for multiple gases. Extended monitoring will tell if there is a problem. With some gases your ability to sense them degrades with prolonged exposure.

#4

My husband now thinks maybe it’s a dead thing in a vent since one of our cats was staring at the under bed heating vent. Duct taped it off (as well as the sink drain). Now the smell is better but I still keep getting whiffs of it.
I don’t know anybody to borrow any kind of gas tester from. Should I call a plumber if it doesn’t get better?

#5

Vents are required for the plumping to work.

S bends are the seals that stop smells coming from the drains.
When the toilet creates a surge of water down the pipe, the air further down the pipe has to have somewhere to go…

With the air vent blocked, the toilet flush can be flowing uphill, eg in the floor drain’s S bend. So the S bend is filled with very dirty water…

AND/or , the suction * in the pipes may suck the water out of the S bends, so that they are no longer air seals. (* “suction”, in this case, is really the atmosphere pushing into the space where the pressure is lower than the atmospheric pressure . )

So air vents should work. You could test by testing for air flow at the vent when the toilet is flushed.

#6

I meant the heating vent, not some sort of plumbing vent. The only thing like that I’m aware of is the one on the roof, right?

#7

a mouse may just be a few days. likely gone before you find it.

#8

I spent last night on the couch because it was making me nauseous (well, more nauseous than the baby already is) and headachy. It was awful. The closest thing to sleep I got was with my legs on top of the dog like a giant bolster pillow under my knees. (To be fair, I did steal his spot.)

I really don’t know about the dead animal hypothesis - if we’re basing this on “the cat was staring at something”, I mean, they do that just to fuck with you. There’s also the possibility, I suppose, that we have a leak somewhere that’s causing mold? Suddenly? Husband is going to take a look around in the attic today.

The weird thing is that it sort of comes and goes. I don’t even know who we’d call at this point but this CANNOT go on.

#9

Some years back, my mom called me, and said that she thought she had a gas leak. So, I went over there, and I thought it was a gas leak, as well. It had started to smell outside, too, and a couple of neighbors also thought it was a gas leak. So, I called the gas company.

That was when my husband came over, and told us that it was no gas leak. He said that there was something dead under the house. Of course, we didn’t believe him.

The gas company guy arrived, did some checking/testing, and sure enough, there was no gas leak inside. The gas guy went under the house to check, and happened upon the problem. It was a BIG possum. It had died under there. When, out of the kindness of his heart, he went to pull it out, it sort of…exploded/fell apart. There were many, many bits.
He quickly came out from under the house, where he promptly vomited. Repeatedly. Then, he left.

After a few hours of my husband and I taking turns (Og, it smelled BAD!) to retrieve all the rotten possum bits, we finally got it all cleaned out. The smell went away after a day, or two.

#10

You know, there might be some benefits to being pregnant after all. Number one being that I can totally beg off exploding possum removal.

There’s definitely nothing big dead under the house. In the walls… god please don’t let it be in the walls.

#11

cats may not be a good indicator for something dead in my experience.

they like hot meals. avoid rotten stuff unless starving.

#12

Dog didn’t seem to notice anything out of sorts, and he’s a scent expert.

#13

So we’ve been around and around and we’re really becoming more certain that it’s probably a dead thing in the walls. We can’t find where, exactly - it’s stronger by the head of the bed but we can’t pinpoint it. Anything we can do to mitigate it until it, you know, takes its course?

#14

is your dog small enough to fit in the vent? rotten animals are dog candy. tie a rope on it’s tail just in case.

if you have the option of having the heating system blow just unheated air then that may dry the carcass and stop the stink.

if it’s a mouse it won’t last long, a day or two. a bigger animal would last longer but also probably be gagging everyone in the house already.

#15

Look in you attic and see if you have a colony of bats that have moved in.

#16

No, he’s quite a big dog. :slight_smile: I do worry that he hasn’t seemed to care too much. He LOVES rotting things. You’d think he’d pinpoint it.

We definitely don’t have bats in our attic (or even our belfry!)