Originally Posted by
hkstroud
Plumber is full of it, or you are misunderstanding. What is peadrain? Do you mean P trap. That is a type of trap used to connect sinks to drain line. Does he mean that there wasn't enough room between the bath floor and the ceiling to in stall a trap for the tub or shower. If he means that he didn't install a trap because there wasn't enough room, then he should be hung up by his thumbs. Sounds like you have a blocked vent pipe. That is evidenced by the fact that if you pour water down the drain the odor goes away. If that plumber did the work, you may not have a vent.
Methane has no odor but sewage does.
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