Sewage smell from floor drain.... not dried

[EdS]

Thanks for the suggestion. I did as you stated, but the drain appears to be flowing well. It would slightly move up and down, like it was breathing, but never backed-up. When all toilets flushed and washer emptied, it moved up about a 1/8 to 1/4 inch for a second, and then right back down again.

The plumber snaked the floor drain, too.

I'm so confused as to what is going on with it. I'm lost. Can you think of anything else to try?

I realize this thread is years old, but the issue is timely for me. My company does office cleaning and we have a couple of buildings with this exact same problem. We're suspecting that the floor drain is either too close to the toilet or that the pipe leading from the floor drain has insufficient slope to prevent backwash from the toilet. My suggestion is to install a rubber one-way valve in the floor drain. They allow water to flow through the drain but prevent odors and bugs from coming up. They cost about $40.00.