Smell of rotting cabbage in d/s bathroom. Is it methane?

It,s probably coming from the sink.Put drain cleaning chemicals down the plug hole also the overflow.

That's probably your answer, down the plug hole AND the overflow on all the sinks & the bidets etc.

Spanish drains have a bit of a reputation for ponging..........

Hi i was advised a while ago that the water levels in the p traps under the sinks will have dried up...If you try going round every sink in the house with the taps on for a munite so that the pee traps can reach a water level.. hope this helps 

As per all above, don't forget to flush properly after chemicals has been used, if there's a gully in the floor, make sure it's flushed with the  water and all sink, gully traps filled with water so their not dry and keeps all bad smells coming from the drainage. Especially floor gully trap tends to dry out letting bad smell in.

Methane is odourless by the way, it is sulphide, agree with above

Thanks.  Hubby has flushed out drains.

He says it was the traps that had probably dried out allowing gases

to float up into room.

Fingers crossed, it seems to have worked.

Thanks so much.

Hubby has flushed out drains.

He says it was the traps that had probably dried out allowing gases

to float up into room.

Thank you.

Anne.

On a similar theme...

i spent 2 years trying to sort out a pong in one bathroom.    I bleached it a lot, steamed it, sealed every small gap with sealant...... yet it returned!

i boroscoped the drains, put odour absorbers and air freshners in the room and yet I was beaten time and time again.

it wasn’t until I went to a forensic level investigation  that i found the issue....

when the drain was unscrewed from the ahower based, all in the drain trap looked well.  When i refitted the cover and tightened it up the plastic pillar for the screw was offset and when tightened hd a crack that allowed the water in the trap to leak out.

i fixed and sealed the crack, pong now gone!

spent hrs in there to get to what was actually and easy fix!