intermittent sewage smell inside

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Caveat

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Hi

Getting a fairly strong sewage smell from either or both bathrooms which seems to be worse when the house is left all day - returning in the evening, 3 or 4 flushes of the toilet(s) seem to improve things. Septic tank seems to be clear.

However, where the U-bend actually goes into the ground and meets the larger plastic waste pipe, I've noticed there is a gap of about a centimeter all around - I'm sure this shouldn't be like this and I'm guessing that's where the smell is coming from. Has anyone seen this before or do you have any suggestions?

If the 'gap' is the problem, any ideas on how to remedy this?

Thanks
 
I presume the setup is the U-bend meets the soil pipe which is encased in a concrete floor. The soil pipe then goes to the AJ outside to connect up to the septic tank?

It sounds as though the soil pipe does not have a proper gradient on it, so is not flowing properly leading to a build-up of smelly stuff. Flushing a few times is replacing this smelly stuff with fresh water.

I have a similar setup on my pipe (u-bend into soil pipe with a gap), but due to some last minute alterations, the soil pipe is above the concrete floor along the wall. I haven't had any smells out of it, so that is what makes me think it is the gradient. There's supposed to be a rubber seal on the u-bend that fits with the soil pipe (otherwise I'd be ankle deep in sewage!), but maybe this wasn't fitted on yours? You could try poking a piece of wire down the gap and see if if hits the seal? If it doesn't or the seal is badly fitted, I suppose you could seal it up with some rubberised mastic? (But I'm not a plumber, so you'll have to wait for some proper advice on that!).
 
yoganmahew said:
I presume the setup is the U-bend meets the soil pipe which is encased in a concrete floor. The soil pipe then goes to the AJ outside to connect up to the septic tank?

It looks that way - is there another possible set-up?

It sounds as though the soil pipe does not have a proper gradient on it, so is not flowing properly leading to a build-up of smelly stuff. Flushing a few times is replacing this smelly stuff with fresh water.

Makes sense to me - I assume there's no straight forward way to introduce a gradient with a minimum of fuss?

I have a similar setup on my pipe (u-bend into soil pipe with a gap), but due to some last minute alterations, the soil pipe is above the concrete floor along the wall. I haven't had any smells out of it, so that is what makes me think it is the gradient. There's supposed to be a rubber seal on the u-bend that fits with the soil pipe (otherwise I'd be ankle deep in sh*tty water!), but maybe this wasn't fitted on yours? You could try poking a piece of wire down the gap and see if if hits the seal? If it doesn't or the seal is badly fitted, I suppose you could seal it up with some rubberised mastic? (But I'm not a plumber, so you'll have to wait for some proper advice on that!).
Click to expand...

Thanks YM - I'll check for that seal tonight - could there be any potential problems in doing a DIY mastic job do you think?
 
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Caveat said:
Thanks YM - I'll check for that seal tonight - could there be any potential problems in doing a DIY mastic job do you think?
Click to expand...

It's what I'd do, but as I say, I'm not a plumber! (I don't know if there should be an air gap, but I doubt it as I would expect my bathroom floor to be swimming in it!).

I was rather hoping that some of the AAM plumbers would respond, but I forgot that they are all on holiday!
 
OK thanks

I should maybe mention that you can actually hear the flushed water echoing around where it joins the external pipe - so it would sound like a seal is lacking!

Never examined toilet plumbing that closely until now (!) so I'll check other connections and see if the gap is as big.

Cheers
 
hi
just a thought but the smell should not come into the house when a blockage occurs if the toilet is vented! no expert myself though.
 
Thanks for info - but couldn't find much on diynot.

I'm pretty sure toilet isn't actually blocked - it's just this smell.

Have had opportunity to check a few other toilets - two of which were of a similar design/set-up and there didn't seem to be any gap whatsoever.

With my own, I can even see the waste water splashing up to within a few centimeters of the lip of the pipe if I look down closely where the bend meets the pipe - this can't be right.

Maybe a proper plumber is the route but I'd really rather not as I'm sure this is easy enough to rectify.

Previous owner was a builder who built the house himself - although probably not an expert in all aspects I reckon he did more or less everything himself, including seemingly the unorthodox plumbing...:rolleyes:
 
There should be a rubber seal where the bend meets the pipe.
[broken link removed]
Does the bend look like this. You can see it comes with a rubber seal at the end which fits into the pipe in the ground. You shouldn't be able to see anywater splashing around..
Maybe get a new one of these in homebase or B&Q.
 
Thanks Beldin

No - where the bend meets the pipe, it just seems to be directed inside the larger 'wavin type' orangey pipe which leads directly into the ground - and of course with this very noticable gap all around.

Looks like maybe just a lazy way of doing things or something?

If it's as simple as getting one of these in your pic then great!

Cheers
 
I had the same problem in my ensuite. Checked septic tank and all was fine. When plumber came back to look at the problem it turned out that there was a gap in the connection between two pipes of different sizes on the ouflow from the toilet. Took 2 minutes to fix, he just fixed the connection to make a proper seal. We had the exact same problem in the kitchen with smells and it turned out that there was no u-bend on the diswasher outflow which meant that nasty smells from the septic tank could fine their way back to my kitchen - not pleasant.
 
if you think there is a gap after the built in trap in toilet. then there will be a very bad smell. buy a tube of clear silicone and cut the nossle to the required thickness of sealant needed and seal around gap. make sure the surface is dry. this will cure your smell problem without removing the toilet to replace mutlikwik seal!
 
it would be a much cleaner and still pretty simple job to detach the toilet and fix a proper seal, rather that messing around with sealant - there should be a stop valve on the feed into the toilet cistern - just turn off water, detach everything and get a proper connector.
 
It could possibly be a blockage in one of your main pipes - particulary if the smell is coming from more than one source. I had a very similar problem in the past and got DynoRod out to blow out the blockage, sorted in 15 mins for about €150 or so...
 
If the smell is IN the bathroom(s) it's most likely that the water seal in the toilet pan is gone !! Check this first as it's the most common.

If it is this there are a few causes to check out.

1.Evaporation
2.Self Siphonage
3.Vaccum

As for the gap on the 4" pipe, it's most likely about a 2mm gap and it is normal. There is a rubber seal on the inside of the female connection.

http://www.dbh.ie
 
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