Paradiceau
New Member
First of all, thank you to the forum for all the great information.
I have read many posts on various threads dealing with sewer odors in bathrooms etc..
I built a house in the mountains which is on septic and the owner notified me of the following after two months of use:
Very strong sewer odor in master bath.
The bathroom has twin lavatories, toilet and shower.
All fixtures are installed with traps and vented per the UPC.
All traps are filled with water.
When he closes the lavatory drains with a popup plug and tapes off the shower drain the odor stops, (I find this interesting because the lavatory overflow is still drains into the P trap.) Because of the overflow there is still a path for gas from the inlet side of the trap to the interior of the bathroom.
He has opened the two way clean out immediately outside the bathroom in an attempt to relieve any "back pressure" from the tank. This had no effect on the odor.
The DWV system was tested per code during the rough plumbing stage. I don't think any drain or waste piping was damaged during construction, the smell being stopped by closing and sealing drains would support that I think.
I am wondering if a change in atmospheric pressure could provide enough resistance to the venting to create this situation? But the traps are working as they should apparently......
I did extend the fixture vents another sixteen inches above the roof, 6:12 pitch.... Maybe this will help.
There are no windows in the bathroom.
I discussed this with the plumber who did the house and he is puzzled as is my partner who has decades of home building experience...
Thanks for reading this and I really appreciate any constructive advice!
I have read many posts on various threads dealing with sewer odors in bathrooms etc..
I built a house in the mountains which is on septic and the owner notified me of the following after two months of use:
Very strong sewer odor in master bath.
The bathroom has twin lavatories, toilet and shower.
All fixtures are installed with traps and vented per the UPC.
All traps are filled with water.
When he closes the lavatory drains with a popup plug and tapes off the shower drain the odor stops, (I find this interesting because the lavatory overflow is still drains into the P trap.) Because of the overflow there is still a path for gas from the inlet side of the trap to the interior of the bathroom.
He has opened the two way clean out immediately outside the bathroom in an attempt to relieve any "back pressure" from the tank. This had no effect on the odor.
The DWV system was tested per code during the rough plumbing stage. I don't think any drain or waste piping was damaged during construction, the smell being stopped by closing and sealing drains would support that I think.
I am wondering if a change in atmospheric pressure could provide enough resistance to the venting to create this situation? But the traps are working as they should apparently......
I did extend the fixture vents another sixteen inches above the roof, 6:12 pitch.... Maybe this will help.
There are no windows in the bathroom.
I discussed this with the plumber who did the house and he is puzzled as is my partner who has decades of home building experience...
Thanks for reading this and I really appreciate any constructive advice!
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