Leak 1 litre per hour

JohnB47

I would strongly back those saying that one of the loos could be the problem. Had it myself recently and it's pretty hard to detect. The problem was a seal, a known problem and easily replaced.

Try this. Inspect the loo around five minutes after the last flush, when things have calmed down. Get a piece of loo paper and wipe it over the back of the pan, above the water line to dry it off. Then watch this area closely, using a torch if necessary. You may see a gentle stream of water running down.

Not much, just a slow slick running down.

On mine, this was sometimes enough to actually agitate the water slightly. On other times the water didn't move.

Green_hopeful

JohnB47 said:

I would strongly back those saying that one of the loos could be the problem. Had it myself recently and it's pretty hard to detect. The problem was a seal, a known problem and easily replaced.

Try this. Inspect the loo around five minutes after the last flush, when things have calmed down. Get a piece of loo paper and wipe it over the back of the pan, above the water line to dry it off. Then watch this area closely, using a torch if necessary. You may see a gentle stream of water running down.

Not much, just a slow slick running down.

On mine, this was sometimes enough to actually agitate the water slightly. On other times the water didn't move.

I tried wiping the loo bowl a bit on the loos. None of them were wet. The shower tray was a bit wet so I have left a jug under it to see if it is dripping when pressure changes. 

I checked the outside tap. I have left a bucket under it and there are no drips. I pulled the tumble drier out and can see the pipe as it goes through the wall and can’t see any damp. 

I listened on the top floor to see if I could hear any drips in the tanks. 

MikeJXE

One more shot,

lift the lid of the inspection chamber outside your home, make sure you lift them all if there is more than one,  if there is a leak it is bound to show up there

If it doesn't then the leak is either outdoors or under your floors. 

Green_hopeful

MikeJXE said:

One more shot,

lift the lid of the inspection chamber outside your home, make sure you lift them all if there is more than one,  if there is a leak it is bound to show up there

If it doesn't then the leak is either outdoors or under your floors. 

Yes going to do that tomorrow if it’s not raining. We have at least 4 manholes to check. Need to do it when no one else is home because obs we don’t want them to be using the water. 

MikeJXE

Some of the chambers might be storm water you need to determine which are foul. 

You can do that by running a tap or flushing a toilet.

Any water may take a long time to drain away depending on the fall and 1 litres an hour will take some spotting after the initial tests 

MikeJXE

Bare this in mind also

If you are in an old house the underground drainage may not be airtight leading to leaks out and also in especially if the water table is high in your area 

GDB2222

One litre an hour is not going to be at all easy to spot, if you lift the manhole covers. It’s only a tablespoon once a minute. 

Incidentally, if you’re on sandy soil, that amount could just disappear into the void under the house and you would scarcely be able to detect it.

Green_hopeful

In no particular order. Our rain water goes into soakaways so hopefully not too much into the foul sewer. It is a really small amount to find as a flow. Kids had moved the jug from the shower this morning before I got to check it so will try that again now. We are on heavy clay so any water is likely to stand. The water meter hasn’t been updating online so will check that again tonight. 

JohnB47

Sorry if you've already checked these but some more thoughts.

Many houses have drainage from bathroom and kitchen sinks going outside and you can actually see water running out of them into a gully, when in use. Once all use has stopped for quite a while, have you had a look at these pipes to see if there's a slow drip there? 

Other thought (perhaps unlikely), could it be a faulty washing machine inlet valve? A bit of grit in the seal would allow a small amount of water to get into the machine and you wouldn't know it.

Depends how big to flow is and how often you use the machine. It would become obvious only when the water level could be seen at the bottom of the drum and if you use the machine very often, you may never see that. Has happened to a friend.

Lastly, I'm sure you've had a good look at all if the pipework under the kitchen sink - that's where most of the joints and connections are.

MikeJXE

Green_hopeful said:

In no particular order. Our rain water goes into soakaways so hopefully not too much into the foul sewer. It is a really small amount to find as a flow. Kids had moved the jug from the shower this morning before I got to check it so will try that again now. We are on heavy clay so any water is likely to stand. The water meter hasn’t been updating online so will check that again tonight. 

Bold highlight ? you have been checking the actual water meter not the online one I presume ?

The jug under the shower, ?  checking for leaks under things is best done with absorbent paper like toilet or kitchen roll