Smell from drains

We had the same problem and was told that in Spain the toilet system is not allowed to be vented to atmosphere like the U.K. stack pipes. So you can have a situation where the sewage vents out of the nearest exit point. In our case this was the downstairs bathroom. Contacted Unblockarod who said this was a common problem and they promptly put a u-bend into the main exit pipe under our house. Cured the problem instantly. Dabe

Lots of really good advice. Many thanks, will definately try what has been suggested.

We had problems with two of our bathrooms upstairs when we bought our house. Removing the bidet in one bathroom did not fix the problem. One plumber I had, put a u tube in the outlet pipe in the under-build but that did not fix the problem either.
I eventually found a plumber who was fully qualified and ask him if he could fix the problem. As somebody has already said that houses in Spain do not have a vent to atmosphere as they do in the UK. He did not say they were not allowed here. To fix both bathrooms he broke into the outside walls upstairs at floor level to give access to the down-pipes and then added a pipe that goes up to the roof level.
We have not had a problem with any smells since.

We had this problem in our shower, we have had the smell for about 18 months tried everything but still had the sewage smell. We have sorted it. The waste in the shower has a square grill, approx 3 x. 3 inch’s, take this out and you will see a round plastic tub with a metal handle on it, this plastic (tub) sits in a bowl of water with the drain at one side, give metal handle half turn and it comes out. Ours had some hair stopping the tub sitting properly which allowed the smells to bypass this valve (tub). Cleaned it all up, no more smells, at last.

Maybe from sewers?

Hi I am a plumber and have worked and lived in Spain.The problem with the drains are from poor workmanship and using the wrong traps+not using solvent weld on the joints also they have not adhered to strict regulations like the UK where the District Surveyor inspects the pipe work and witness an Airtest.If the drains are not up to spec the building cannot get a Certificate of Habition which means its Un Mortgageable.Also the Traps do dry out when not in use.

you,ve hit the nail on the head, Spanish don't build like uk in any way or form ,dry traps (if any) allow smells to rise through sanitary ware outlets,the cooler and wetter months will soon be with us ,then you will realize the the Spanish don,t build for cold or wet weather! wacth out for water ingress thru the ceilings and walls,