Sewer Gas

Help

The drain in my basement bathtub smells of sewer gas really bad. The bathroom has been finished for about a year and we have not had this problem before. The tub gets used almost daily, and is draining fine. Is the vent pipe possibly blocked or something? It has recently been extremely cold here. Do we need to check somthing in the attic? Please help, I cannot stand the smell anymore.

Grumpy

I think we just covered this topic. Perform a search for answers. Or maybe it was the DIY forum instead? I get confused.