We have a sewer smell coming from the downstairs bathroom.

When was the last time the sink, tub,or shower was used downstairs.. If it has been more than 15 days or so, the trap at one of these fixtures may have started to dry out and is now allowing sewer gas to enter the house.

To fix this... just run water down the drain and remember not to let it go much more than 15 days or so.

Otherwise, I would tell you to look for any other abandoned drain lines that may not be capped properly... an old laundry trap or similar.

Also wondering if you can isolate to sink or shower drain... we can recommend a good fix to clear the drains is needed.

Sometimes soap/hair/chemicals combine at sink drain and can really stink. Here, I remove the nut under the sink and then remove the stopper and then clean all this, then reinstall stopper (but first clear and deodorize the drain).

Let me know what you think... MARK

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