2 Bathrooms beside each other 1 has sewage smell.

[RSimpson]

We recently bought a house that has 2 bathrooms basically beside each other in 2 rooms. The main bathroom has no sewage smells. The Bathroom beside it in the master bedroom has sewage smells after using the toilet regardless of #1 or #2 . I have noticed that if someone is taking a shower in the main bathroom that the toilet in the master bathroom will have the water draw down like it is being sucked out. We do have a septic system. I am wondering if this could be a trap issue in the master bedroom or if anyone could help point me in the right direction. So far the cure is to make sure the master bedroom toilet is flushed after every use but the smell is still somewhat there just not as prevalent.

 

[HWSleuth]

Check seal on toilet. The fact that water level is sucked down sounds like broken or stopped vent.

 

[RSimpson]

Check seal on toilet. The fact that water level is sucked down sounds like broken or stopped vent.

I was thinking maybe the vent or the trap not properly installed. This bathroom appears to have been installed after the house was built. It is really hard to discern at this point I was hoping that the experts could help point me in the right direction. The water draw down in the secondary bathroom is hopefully a major clue.

Another thing is that the sink in the second bathroom has no problems and the smell only tends to be from the toilet.

Any advice is really appreciated.

 

[Jeff Handy]

Sounds like there is a partial clog in the drain line leading to the septic.
Anywhere between that toilet and the septic tank.
Probably pretty close to that bathroom.
You might have to pull the bedroom toilet, or both, and have the drain lines snaked out.

 

[Geofd]

If your getting a smell from your toilet have you changed the wax ring that could be your smell, just changed one yesterday, not for that reason , but it was totally flattened out no smell but I'm sure it's functionality was going

 

[RSimpson]

Replaced the wax ring in the affected bathroom with no luck the smell remains. The bathrooms are located exactly side by side and they are sharing the same drainage. There is no smell from the sinks or bathtubs but if someone is taking a shower in the main bathroom the water in the toilet in the second bathroom draws down like it is pulling suction.

What keeps throwing me off is that the smell goes away as long as you flush immediately after you use the toilet. But while you are using it you can smell sewage almost like the trapped gasses get released while you are using it.

Maybe it would help if I explained that these are low water toilets not sure if there is a pump involved or not on them but they use way less than a gallon of water per flush.

 

[Geofd]

Sounds like the toilet is getting siphoned while your showering loosing your trap seal

 

[Geofd]

Replaced the wax ring in the affected bathroom with no luck the smell remains. The bathrooms are located exactly side by side and they are sharing the same drainage. There is no smell from the sinks or bathtubs but if someone is taking a shower in the main bathroom the water in the toilet in the second bathroom draws down like it is pulling suction.

What keeps throwing me off is that the smell goes away as long as you flush immediately after you use the toilet. But while you are using it you can smell sewage almost like the trapped gasses get released while you are using it.

Maybe it would help if I explained that these are low water toilets not sure if there is a pump involved or not on them but they use way less than a gallon of water per flush.

If they were on a pump I think you would hear it cycle and you may also hear the check valve close, open the tank cover if it has a handle, flapper and ballcock I think the lowest flow toilet is 1.28 Gpf unless it's an air assist flush type, the internals would look totally different

 

[HWSleuth]

As Geoff notes, if commode or other drain is being siphoned, there’s a vent problem. Your vents should be visible in attic. Maybe commode was installed without a vent. Or, vent installed is stopped up or restricted.

 

[RSimpson]

As Geoff notes, if commode or other drain is being siphoned, there’s a vent problem. Your vents should be visible in attic. Maybe commode was installed without a vent. Or, vent installed is stopped up or restricted.

I will check but since both toilets share the same vent line would I not have the same issue in both bathrooms? I did look at my roof this evening and I do notice that the vents coming out of the roof do not have any covering or protection I may have to get up there and check to see if they are blocked by birds nests or something else

I will also check the internals of the toilets Thanks Geofd.

Thanks for all the replies this is very helpful.

 

[Jeff Handy]

Vents going out the roof don’t need any coverings.

Is there an attic above these bathrooms?

Sometimes a vent running in the attic turns horizontal for awhile, and it can fill up with water, which blocks the air movement.

I still vote for a partial drain blockage, which is a common cause of a toilet bowl water level being sucked partially down.

 

[Geofd]

A long time ago I did run into a toilet that had an internal crack and the bowl kept draining

 

[Geofd]

Jeffhandys got a good point, if there is something in the toilet might be acting like a wick draining water that way,
This might be a little bit of a pain but if both
toilets are the same swap them and see what happens

 

[Twowaxhack]

If the toilet siphons out in the adjacent bathroom when you take a shower then you more than likely have a clogg/partial clog in the piping or your septic system isn’t working properly causing the system to fill up.
When the system fills up and then drains, the toilet will siphon.