Sewer smell

TimeOnTarget

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Alright guys, you’re a group of smart guys so help me out with where to start/ continue my search for why I have a sewer smell in my house.

Every time it gets cold out(today is about -5) I get a sewer smell in My house. My roof vents are not froze over and my traps all have water in them. I’m on a septic system. It started happening about 3 years ago when I finished my basement and installed a full bathroom. The basic plumbing/drains for the basement bathroom had been there for 10 years prior as it was installed in the concrete when the house was built. Obviously the venting for the bathroom was plumbed in at the time of finishing the basement. I’ve read some about the cold air basically creating a down draft and not letting the warm gases escape out the stacks, settling back down the stacks instead. I never have this problem until it gets cold.
Give me your ideas and solutions.
 
I don't use my basement bathroom often and when weather gets cold I often get a funk smell from my sump. All I do to get it better is flush it either take shower in that bathroom or just couple flushes of toilet and let sink run for few till sump cycles couple times. Beyond that I don't know what it could be or why it happens.
 
I don't use my basement bathroom often and when weather gets cold I often get a funk smell from my sump. All I do to get it better is flush it either take shower in that bathroom or just couple flushes of toilet and let sink run for few till sump cycles couple times. Beyond that I don't know what it could be or why it happens.
This has also been my bandaid solution so far. I can’t say for sure but I’d put money on the smell escaping my sump even though I’ve rtv’d it shut.
 
We had a similar problem in a house we were remodeling. Our pumber did a smoke test. Plugged all vents and filled the system with smoke. It's been a few years but I can get details from him if you are interested. mtmuley
 
We had a similar problem in a house we were remodeling. Our pumber did a smoke test. Plugged all vents and filled the system with smoke. It's been a few years but I can get details from him if you are interested. mtmuley
I am interested. Looking for air leaks i assume?
 
I could make a political joke in response to the sewer smell but I will refrain. Good luck with the issue. Happy hunting, TheGrayRider.
 
Depending on how tight your house is, maybe due to the cold weather, your furnace is working harder and turns on more often. It could possibly be pulling air through your vents/traps even though they have water in them.

Do you have a floor drain somewhere you haven't' looked? Like under a boiler, or water heater?

I have also had smells, and it was always a floor drain that dried out.
 
IMO no sump should smell like a sewer.....when we have smells like this as stated, run all showers to fill the pipes that maybe are now dry.
 
Look at the floor drain near the furnace. There should be a condensate line going to it. When it’s really cold and the furnace isn’t producing any condensation due to the dry air and lack of “humidity “ the floor drain p trap can be the source. Just dump some water in the drain and fill the trap.

Hard to say what you have going on without seeing the system. I would look at all drains first. Good luck.
 
As odd as this sounds, I had a hospital project last year that once we finished, one office had a sewer smell. Looked into it, and turns out, the plumber didn't hook up one of the vents. So it was venting into the wall. Had to open the wall up and make the connection so it would actually vent.

Another thing is just using the drains. Do you have a trap under the sink? A trap does just that and holds water to prevent the sewer gases from coming out. If the sink is never run, the water in the trap can evaporate and allow sewer gases to travel up and out of the drain in the sink.

Go smell each drain and figure out which one(s) the smell is coming from. Then simply add water!
 
Alright guys, you’re a group of smart guys so help me out with where to start/ continue my search for why I have a sewer smell in my house.

Every time it gets cold out(today is about -5) I get a sewer smell in My house. My roof vents are not froze over and my traps all have water in them. I’m on a septic system. It started happening about 3 years ago when I finished my basement and installed a full bathroom. The basic plumbing/drains for the basement bathroom had been there for 10 years prior as it was installed in the concrete when the house was built. Obviously the venting for the bathroom was plumbed in at the time of finishing the basement. I’ve read some about the cold air basically creating a down draft and not letting the warm gases escape out the stacks, settling back down the stacks instead. I never have this problem until it gets cold.
Give me your ideas and solutions.
I own a septic service business in Montana and get calls often about this. The short answer is that during really cold and really hot days...inversion happens which causes the odors to "settle" into the vents. My solution is to keep your pea traps and drains wet. They also make a charcoal filter that you can put on your vent pipes which seem to help.
 
I have also had smells, and it was always a floor drain that dried out
That is most often the cause. Having done structure and energy audits for commercial and residential buildings, I analyzed tightness and ventilation using blower door equipment to create a negative pressure within the building. Odor problems were commonly due to dry or inefficient drains, but other sources of odors are possible. When flushing a floor drain it's helpful to include some bleach with the water to eliminate the odor. Also, mold sometimes smells similar to sewer odor.
Consider that when it's cold you close up the house and try to seal leakage to the point where a negative pressure may result. Likely you have an idea how "tight" your house is.
If it smells "skunky" like natural gas odor additive, then call the utility complany as they typically will provide a free service to check for gas leakage and/or other unsafe or unhealthy leakage.
 
Drains are kept wet. Floor and traps. I’ve paid extra attention to them all this year as I’ve been anticipating this problem coming back.
 
Ollin Magnetic Digiscoping Systems

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