Very high water bill mystery!

[crowman]

The house was built in 1983 and is a semi.

 

[Joncpi]

I assume your toilet is has a close coupled cistern. It is possible for there to be a small leak from under the syphon into the bowl. This is the only place I can think of, off the top of my head, for an almost invisible leak. If you have an isolator valve on the toilet turn it off over night or alternatively tie up the ball valve. If the cistern drains over night then the problem is a leak under the syphon.

 

[rpm]

Quicker to do the tissue test Joncpi it shows the leakage up in minutes rather than hours.

 

[firemant]

Don't think anyone has asked yet;

How old is the house?
Is your house Detached, Semi, Terrace?
Or is it part of any previously redevelopment, like Barn conversion?

If Detached are there any near neighbours?

I think Snowy is alluding to the possibility that a neighbour is using your water

My thoughts were along that way,but the self emptying CWS may give the lie to that theory.

Some years ago, I had a lock up shop. During some renovations, I discover that the detached garage was wired from the flat above. The wire came from the flat, through the shop to our garage

 

[crowman]

I think Snowy is alluding to the possibility that a neighbour is using your water

My thoughts were along that way,but the self emptying CWS may give the lie to that theory.

Some years ago, I had a lock up shop. During some renovations, I discover that the detached garage was wired from the flat above. The wire came from the flat, through the shop to our garage

To be honest I thought the same at one point as I have a neighbour from he'll who also has the know how to do such a thing due to his job!

Tests suggested so far haven't discovered anything so I think I will have to get someone in to investigate further. I appreciate all the help and suggestions received.

 

[firemant]

That's fine I welcome your questions to hopefully get to the bottom of this. I had the stoptap off for about 3 hours and there was no movement. When the water company guy came he said if there was a leak he could have seen even the tiniest drip showing on the meter.

To be honest I thought the same at one point as I have a neighbour from he'll who also has the know how to do such a thing due to his job!

Tests suggested so far haven't discovered anything so I think I will have to get someone in to investigate further. I appreciate all the help and suggestions received.

Ignoring fora moment the CWS issue - If the neighbour IS using your water,it would only show movement when he is using the water. Say for an outside tap or equipment in garage.

What does CWS supply? Have you a (maybe tank fed) dishwasher and/or washing machine? Could the inlet valves on one of these be passing?

 

[crowman]

CWS is for upstairs sink, bath, shower and toilet. The downstairs sink and washing machine comes off the mains.

 

[Gasmk1]

Then your toilet is more than likely the culprit check the bowl and water will be entering the bowl when not in use

 

[firemant]

Is there an isolation valve on the WC?
If so, buy a bucket. Use the bucket for a while filled from downstairs to flush and don't use other items filled from shower. Monitor the CWS.

Or do the bog paper trick, If you haven't yet

 

[Bogart]

Some meters have a little turbine wheel spinning that shows miniscule water use (that is still significant over time) and easily indicates flow long before a digit will move.

My leak seems more obvious. With my stopcock off the little wheel still turns so my leak is between meter and stopcock. As the distance is some 30m I do not fancy digging up 30m of ground to find it, maybe in summer if we get one!
The problem quoted should be fairly easy to solve with a bit of logic as has been suggested by other contributors.