Shortly after draining the bath tub following a bath there is a sewer smell in the house for a period of 10 to 20 minutes. This just started to happen in February of this year. The house is 16 years old. I anticipated it not occurring once the ice and snow had melted that may possibly be blocking the vent on the roof, however it is still happening. Any help?

I once had to replace a shower drain and trap for a customer because a black gel substance had built up on the pipe (before the trap). It always smelled in that bath after a shower. But you state that the smell is in the house. Does that mean throughout the whole house? Is it worse in that particular bathroom?

Most bad oders in bathroom drains come from rotting hair mixed with grease from the soap. Try this. Tonight before you go to bed pour 1/2 gallon of bleach down the tub drain and let it set overnight. Next morning flush it down with a few large pans of boiling water.( The boiling water's important.) The bleach will start to dissolve and soften the hair and make it slippery and the boiling water will melt the grease and flush the mess out into the main. Now see if that smelly drain doesn't smell sweeter? Hope this helps . Tom