Help - what on earth is going on with my drains

[Flyingsouthwiththeswallows]

Sitting in the Living Room just now, I hear a deep rumbling from upstairs.

Investigating, I have a bath full of bubbles emenating from the bath plug hole.

Flushing the loo next to the bath, causes the water to rise in the loo pan, then release quickly sending more bubbles up through the bath plug.

Flushing the loo in the other bathroom, causes the same reaction. The loo fills to the top of the pan, then quickly releases sending bubbles up through the shower drain.

Back story. This is a newly nenovated property, but I have been fighting a smelly shower for some weeks. I have tried every cleaner imaginable to remove the smell but nothing works for longer than a few days.

I lifted the rodding eyes in the garden last week to check the drains were clear. They were pristine and water flowed clearly when I tried each of the taps.

The only other factor I can think of, is that we had a downpour of rain just before tonights problem.

Help. Could anyone advise what might be happening? Do I need a plumber or a drain specialist? Piglet John are you able to advise what might be happening?

It sounds like there might be an obstruction in the main line of the house. It needs to be looked at immediately before you have a flood on your hands.

It sounds to me more like the blockage is in the house, in the soil pipe.

How old is the house?

Has an additional or modified bathroom or plumbing been fitted since the house was built?

Does anyone flush Sanpro, toys, condoms or wipes down the WC? Or chip fat down the sink?

Start getting personal recommendations of a wrinkly local plumber from people you know and trust. Advertisements on websites where the business pays to be listed and can edit customer feedback are not a good source, even if they are disguised as recommendation sites.

The property is very old (200 years) but was renovated and totally refitted 2 years ago. I am the second owner since renovation but the 1st didn’t really live here. I have been here 9 months

The plumbing was replaced during renovation and no adjustments since except to put a new pressure header onto the Unvented Cylinder.

None of those items flushed down the toilets. Just paper.

No chip fat down the sinks. Occasional coffee grounds but the pots emptied into a bag, so just remnants. I use a dishwasher ona high temperature, 3-4 times a week. Washing machine 3 times a week.

I have had issues with the water in a downstairs loo discolouring as if there is some flush back and the smelly shower drain as mentioned above. Otherwise one of the upstairs loos is slow to flush away occasionally.

Trying to get a plumber in this area is a nightmare. I did have a fabulous one come and look at the unvented cylinder several months ago, but no response from him when I left messages about the smelly shower several weeks ago. I have left messages for him again tonight and am just hoping he will contact me tomorrow.

You don't need a qualified heating engineer, you need a wrinkly local plumber.

Trying to find one is a nightmare Piglet John. I have lived in the area 9 years and everyone has the same issue. They just aren’t there.

I am constantly asking if anyone knows of a good plumber. Electricians are just as difficult.

Would you use Dyno Rod if you were me Piglet John ?

No

Try the Parish Magazine.

What have you put down to clear the blockage?

My bathroom sink was not draining well and the bath bubbling up with water.
I poured some sodium hydroxide down, warm water. ( google safety as it’s very toxic)
There was a unbelievable amount of rumbling in the pipes under the floor. Then a sucking noise as the blockage cleared.

The fact that it is linked to heavy rainfall suggests that the area may be served by combined sewers (ones that take rainwater as well as foul waste) which are quite common with older housing.

Couldn't it be an air block?

No

Update after numerous phone calls.

My plumber has said he can’t help because he thinks it will need cameras etc.

The builder who converted the property has no drain plans but thinks the two bathrooms are connected to the external drains through different outlets, so suspects it is an external (shared) drain issue rather than internal.

I have called the local Water authority who will come out to look at the external drain.

I have also started to look for a local drain company who can come and put a camera through my internal drains if required.

Final update

The water authority have investigated the external drains in my garden and the little road next to my house Both show evidence of very high water levels in the last few days.

They have checked the telemetrics at the local pumping station. There was a very high surge of water at exactly the time I experienced the problem. They believe that the storm outside caused a back up of water in the main drains through the village.

Their theory is that the gas in the drains had nowhere to go and blew back into my house, forcing water and air up through my bathroom plug holes. The toilets were unable to flush because the drains were overloaded.

Clearly I need to talk to a drainage expert to protect my house from a repeat of the issue.

Thank you all for the useful advice and information !!

Aha

You will notice on older houses, the soil pipe runs on the outside of the house wall, and terminates, above the highest opening window, with an open end.

This enables any sewer gas or overpressure to escape harmlessly.

To save effort, people changing the plumbing or fitting new bathrooms often omit this, and have the end of the pipe hidden in a duct in the bathroom, with a Durgo or similar valve which, until it jams, prevents smells (or pressure) escaping.

If you still have any old pipes on the outside wall, an open ended pipe could be added to prevent pressure in the pipes.

Unfortunately there isn’t a single outside pipe Piglet John.

I also have no idea how to find the Durgo.

I phoned a couple of companies this afternoon for quotes to look at the issue. Appears to be an open cheque book scenario.

So if pretty much was an air block then?

"I have had issues with the water in a downstairs loo discolouring as if there is some flush back and the smelly shower drain as mentioned above. Otherwise one of the upstairs loos is slow to flush away occasionally."

sounds like an internal blockage to me.

If there was detritus trapped in the pipes, I suppose a pressure wave might blow the detritus upwards if for some reason the air was unable to escape. But the traps and bends should have only clean water in them unless there is a blockage.

Durgo is likely to be hidden in the boxing in the corner of the room where the waste pipes and soil pipe go. In a modern house this is usually the corner of the bathroom and it continues in the corner of the kitchen below. If the soil pipe continues up and emerges through the roof, no Durgo is needed.

When an alteration or additional bathroom is fitted, the pipes may follow a long and wandering path, encouraging the settlement of blockages.

Do you think the water company were fobbing me off with their explanation Piglet John

They certainly haven’t solved the problem and I am fearful about the next big storm.

I have spent hours on the phone today trying to find someone to come and look at my internal drains with a camera and am worried that a stuck Durgo valve is going to result in either knocking out a wall or lifting my beautiful bathroom floor to get to it.

Probably was a high water level in the drain, and as piglet John says if the water gets above the top of the pipe exiting your house, the pressure in the drains will increase as it rises further or you flush the toilet etc. That raised pressure will push through whichever trap is shallowest which would be shower or basin, so the drain air will bubble out.
The fix is to vent the drain properly above roof level.
If there's no working air admittance valve at the head of the run them you would have the opposite problem where flushing the loo would cause negative pressure and pull the water in the shower trap the other way, which would also cause smells.

Thank you Johnd2

Have managed to find a plumber today who MIGHT be able to come out and look at the issue at the end of the month.

In the meantime he needs to know where my Air Admittance / Durgo? Valve is located. So despite claustrophobia I have crawled through the tiny loft hatch and searched the loft for it today. No sign !!

Does anyone have any ideas where else it might be hidden?

I do have a concealed cistern which is boxed in with the lid super glued down. Could it be in the boxing alongside the cistern?

Would there be more than one valve? i.e. one in each bathroom?

Could it be behind the bath panelling ?

How high would it need to be?

I really don’t want to start knocking down walls looking for it but am struggling and would really appreciate any advice.

Ok my husband, who is not a plumber, but an engineer, who resolved this for my daughter, says if your drains are blocked, which he thinks they are, then you either call dyno rod or start plunging your loo. But likely you need dyno Rod, as they can clear the blockage.

If it's an air lock you go to the highest point in your house and run the taps. But he thinks it's a dyno Rod job.

Have you rang the council? They might be able to help with sewage problems rather than a private company

Thanks Bluntness 100 and please thank your husband. I really appreciate your thoughts.

Things have moved on from the other night and there is no obvious blockage in the system. We have had the drain cover in the garden up and everything appears to be flowing fine.

However, there was obviously a serious issue the other night and I am worried about a reoccurence. The water authority have blamed it on a flushback / blowback of sewer gas in the main system which chose to present in my house. Two plumbers have told me they think my Air Admittance (Durgo) valve may be faulty. They say that could explain the previously smelly shower and the way the pressure from the mains impacted my system.

I really need to find this valve. I have spent most of the day looking for it and just wish I understood enough to know where it might be located.

The WC exits through a 100mm (ish) diameter soil pipe, probably amost horizontally. It proceeds until it can join up with the main soil pipe stack, which is probably vertical, probably in the corner of a room such as a bathroom, and probably boxed in to make life difficult conceal it.

This is such a big pipe that you should be able to follow or find it.

The Durgo ~(assumin there is one) will be on the top of that soil pipe, it will be a bit higher than the highest fitting that drains into it (probably a wash basin) so it is often hidden inside the boxing in the bathroom corner around shoulder height.

other waste pipes, such as the kitchen sink, may connect to the stack when it passes through rooms below.

It might run in the floor between the joists, if they happen to run in that direction, but it is so big that you can't cut a hole in joists to run it through.

preferably the distance between the WC and the soil stack will be a metre or so. Long horizontal runs of pipes are very prone to blockages.

The pipes first put in by the housebuilders are less likely to be badly run than pipes for an additional bathroom that has subsequently been shoehorned in.