We're getting a musty smell from the toilet and no amount of cleaning
(bleach and toilet cleaner, and bleach blocks) will shift it. No signs
of leaks, and I've replaced the seat and lid. It's been like this since
we moved in - about a year.
Any ideas please?
Check where the soil pipe vents. Sometimes there is an air admittance
valve in the bathroom - possibly boxed in? - rather than being vented to
the outside air. These can sometimes go wrong and need sorting out or
I had this - The toilet had a plastic pipe that went into the earthenware
pipe in the floor. Some of the sealing fins in the plastic were distorted
and were letting sewer smells up. There was never a visible leak as the
water could always flow down.
+1. We had exactly the same problem, but disgiused by the wash basin
drain smelling. The wash basin, where the plug fits, had a ledge under
the plug. Matter would collect on the level ledge and start to smell.
It was identical to the kitchen sink drain, which I had to replace a
couple of years ago because of the constant smell. She would put
cleaner down it, the smell would disappear for a day or two, then
A very poor design, having a ledge in the drain where matter can
collect. That might be your problem. I replaced the entire wash basin
drain with a modern button operated plug.
The plastic pipe of the toilet, where it goes into the earthenware pipe
in the floor, which I had fitted 15 years before, had developed a
slight air leak, allowing sewer smells to escape. A bit of sealer fixed
We had just this problem. Possibly caused by hot bat water *gumming* up
the vent seal. AAV from a different manufacturer seems to have cured
A much more obscure problem with a vague sewery pong in a ground floor
area served by two toilets (we have 5 in total:-) turned out to be a
small leak where the builders had not fully sealed a new soil pipe to
the benching in the inspection pit. A partial blockage elsewhere caused
foul water to leak into the drain trench and trickle back under the
house through the pea shingle surrounding the pipe.
The *drains test* by building control should perhaps have spotted this?
The bath/sink drain to a separate pipe, which goes in to the gutter
downpipe. The toilet is separate. I remember the plumber did lift the
drain cover, and asked me to flush some toilet paper down so he could
see which 'branch' was ours. He didn't mention any problem at that end.
The vent and soil pipe were replaced about 6 months ago, and the toilet
relocated slightly. It's the same smell before and after. Not really
drains, more musty, like wet paper. The bare boards around and the
ceiling below all look fine.
The plumber did about 6 months ago - no problem noted. The neighbour
told me there was a blockage a few years back - the drains came up in to
the gardens, But apparently that was fixed then. The smell definitely
comes from the toilet.
Yes, to put the bleach blocks in, and I did replace the valve a few
months back. Nothing obviously untoward. The cistern and pan have also
been separated and cleaned when the toilet was moved 6 months back. The
smell was there before and has remained.
As I say, it's not unpleasant sewage type smell, more this musty, dank
sort of pong.
By 'musty' do you mean drains-related? Could there be something amiss
with the arrangements for the cistern overflow such that it goes
directly into the soil pipe bypassing any form of trap, thereby letting
drains smells into the room?
Is the smell definitely the toilet (not sink/shower/bathtub)?
Maybe a long shot, but have you tried *really* cleaning under the rim. I
mean physically with a scourer, not just squirting a bit of bleach there.
You need to be careful, don't go too fast, as you could pinch your
fingers if the profile narrows.
After being plagued with a smell on and off for ages, I finally did this
out of desperation. The water came out *black* with some sort of mould.
This is despite repeated cleaning with toilet duck.
Clingfilm over the bowl can be useful to help eliminate/isolate smells.
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