Water leak detection and Buildings Insurance
Discussion
A big thumbs up to ADI.
Frank arrived at 9.30 and began by pressure testing bits of the hot and cold water supply pipework around the house. By 10.30 he'd found a pressure drop on one length of pipework between the softened cold water feed from the cold water accumulator to the dishwasher on the kitchen island.
Next he pumped that pipework full of nitrogen and then went around with a detector, following the pipework route under the floor heading towards the island. It went ballistic around 12 inches from the kitchen sink / dishwasher.
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Small jackhammer was then broken out. Frank, amazingly did all of this in the space of 1 kitchen tile :
So that is one tile broken out, go through 100mm of screed, avoid the wet underfloor heating and find the cold water, softened cold water and hot water pipes.
With compressed air now filling the pipework Frank used washing up liquid to find the leak - although the hissing noise was a complete give away.
Right now Frank is putting in some new pipework...
Frank arrived at 9.30 and began by pressure testing bits of the hot and cold water supply pipework around the house. By 10.30 he'd found a pressure drop on one length of pipework between the softened cold water feed from the cold water accumulator to the dishwasher on the kitchen island.
Next he pumped that pipework full of nitrogen and then went around with a detector, following the pipework route under the floor heading towards the island. It went ballistic around 12 inches from the kitchen sink / dishwasher.
[urlSmall jackhammer was then broken out. Frank, amazingly did all of this in the space of 1 kitchen tile :
So that is one tile broken out, go through 100mm of screed, avoid the wet underfloor heating and find the cold water, softened cold water and hot water pipes.
With compressed air now filling the pipework Frank used washing up liquid to find the leak - although the hissing noise was a complete give away.
Right now Frank is putting in some new pipework...
Edited by AnotherGuy on Monday 30th January 14:15
AyBee said:
Impressive stuff! So was all the water just seeping into the ground below?
The floor construction is hardcore, followed by concrete base, waterproof membrane, then Celotex with pipework underneath, then 100mm screed with underfloor heating pipes embedded in it. Then tiled on top.So the water leaked underneath the Celotex and onto the concrete base which had a slight slope to it so it just all ran to the back edge of the kitchen floor where it then ran down into the bare earth underneath - my hunch about the water collecting in the corner due to being on a slope seemed to be accurate.
Still unlikely to be an insurance claim as there's still no damage evident - despite the ground beneath my house literally being sodden.
Perhaps I can feel slightly better that my water bills will at least now be lower.
AnotherGuy said:
Next he pumped that pipework full of nitrogen and then went around with a detector, following the pipework route under the floor heading towards the island. It went ballistic around 12 inches from the kitchen sink / dishwasher.
Amazing that the nitrogen can pinpoint the leak with that accuracy - you'd think it would just seep out of the floor all over the place.Sheepshanks said:
Amazing that the nitrogen can pinpoint the leak with that accuracy - you'd think it would just seep out of the floor all over the place.
I seen something similar demonstrated and was told that rather than ‘smelling’ the nitrogen, the machine was listening for an inaudible hiss of the gas being released.Rough101 said:
Sheepshanks said:
Amazing that the nitrogen can pinpoint the leak with that accuracy - you'd think it would just seep out of the floor all over the place.
I seen something similar demonstrated and was told that rather than ‘smelling’ the nitrogen, the machine was listening for an inaudible hiss of the gas being released.
Sheepshanks said:
Rough101 said:
I seen something similar demonstrated and was told that rather than ‘smelling’ the nitrogen, the machine was listening for an inaudible hiss of the gas being released.
Hmm...would nitrogen, having bigger molecules than oxygen, be noisier than plain compressed air? 
OutInTheShed said:
Sometimes nitrogen has some helium added for leak detection.
We used to use Nitrogen for pressure testing some kit where oxygen wasn't wanted, so compressed air wasn't ideal.
Me too, when I was working.We used to use Nitrogen for pressure testing some kit where oxygen wasn't wanted, so compressed air wasn't ideal.
No good trying to "sniff" nitrogen as there's so much in the air to start with, but Helium is easily detectable.
OutInTheShed said:
The question is, how did it fail and how will the rest of it fare?
My understanding was that if you bury copper pipe, anywhere where it might be damp, you need to protect either the soldered joints or the whole pipe depending on who you talk to?
The solder joint on the 90deg bend failed. I run twin cold water accumulator tanks in an unvented system - so that I get 3 bar pressure at the tap - as I really like my rainfall showers.My understanding was that if you bury copper pipe, anywhere where it might be damp, you need to protect either the soldered joints or the whole pipe depending on who you talk to?
That also means 3 bar pressure to the dishwasher, so the hammer action of on/off water delivery plus high(ish) pressure is going to put joints under some strain.
The whole system was pressure tested for 24 hours prior to commissioning 5 years ago. Both my uncle and ADI plumber agree that its unusual that it's failed now - basically joints normally fail immediately or after many, many years of continuous hot / cold water cycling - like a central heating system, but not normally on a cold water feed to an appliance. Literally just bad luck.
And just to be clear - the pipe wasn't buried as such. There is a concrete subfloor, with a polythene damp membrane on top, then the pipes covered in Celotex and then the screed of top. The pipes are free to move within the Celotex, it a completely damp free environment - unless of course the pipe is pissing water all over the subfloor
Hindsight and all that, but unjoined plastic pipe would surely have been better for those runs.
Maybe our area is unusual but three bar doesn’t seem that high - our new pressurised system is balanced at that off the main. Cold (hot was gravity) was higher than that before - never caused us an issue, but I do recall a neighbour having an issue with, as it happens, a dishwasher, and having to fit a pressure reducer.
Maybe our area is unusual but three bar doesn’t seem that high - our new pressurised system is balanced at that off the main. Cold (hot was gravity) was higher than that before - never caused us an issue, but I do recall a neighbour having an issue with, as it happens, a dishwasher, and having to fit a pressure reducer.
AnotherGuy said:
OutInTheShed said:
The question is, how did it fail and how will the rest of it fare?
My understanding was that if you bury copper pipe, anywhere where it might be damp, you need to protect either the soldered joints or the whole pipe depending on who you talk to?
The solder joint on the 90deg bend failed. I run twin cold water accumulator tanks in an unvented system - so that I get 3 bar pressure at the tap - as I really like my rainfall showers.My understanding was that if you bury copper pipe, anywhere where it might be damp, you need to protect either the soldered joints or the whole pipe depending on who you talk to?
That also means 3 bar pressure to the dishwasher, so the hammer action of on/off water delivery plus high(ish) pressure is going to put joints under some strain.
The whole system was pressure tested for 24 hours prior to commissioning 5 years ago. Both my uncle and ADI plumber agree that its unusual that it's failed now - basically joints normally fail immediately or after many, many years of continuous hot / cold water cycling - like a central heating system, but not normally on a cold water feed to an appliance. Literally just bad luck.
And just to be clear - the pipe wasn't buried as such. There is a concrete subfloor, with a polythene damp membrane on top, then the pipes covered in Celotex and then the screed of top. The pipes are free to move within the Celotex, it a completely damp free environment - unless of course the pipe is pissing water all over the subfloor
I had rising damp in the hall, which was in the middle of the building, at a 1970s house I owned about 30 years ago.
Plumber diagnosed it as copper central heating pipes having been attacked by the concrete in the hall floor screed, and rerouted the entire ground floor of the system via the first floor.
It never occurred to me to talk to my house insurers.
Plumber diagnosed it as copper central heating pipes having been attacked by the concrete in the hall floor screed, and rerouted the entire ground floor of the system via the first floor.
It never occurred to me to talk to my house insurers.
Sheepshanks said:
Hindsight and all that, but unjoined plastic pipe would surely have been better for those runs.
Maybe our area is unusual but three bar doesn’t seem that high - our new pressurised system is balanced at that off the main. Cold (hot was gravity) was higher than that before - never caused us an issue, but I do recall a neighbour having an issue with, as it happens, a dishwasher, and having to fit a pressure reducer.
Ours is regulated to 3 bar. The incoming mains is about 9 or 10. Combi boiler is only wanting up to 4.5 bar IIRC.Maybe our area is unusual but three bar doesn’t seem that high - our new pressurised system is balanced at that off the main. Cold (hot was gravity) was higher than that before - never caused us an issue, but I do recall a neighbour having an issue with, as it happens, a dishwasher, and having to fit a pressure reducer.
I'm not liking the black colour of the copper pipe.
I would be wondering about earth bonding.
QBee said:
I had rising damp in the hall, which was in the middle of the building, at a 1970s house I owned about 30 years ago.
Plumber diagnosed it as copper central heating pipes having been attacked by the concrete in the hall floor screed, and rerouted the entire ground floor of the system via the first floor.
It never occurred to me to talk to my house insurers.
Copper in direct contact with concrete can corrode to a hole in only a few short years. And it never leaks in a convenient place Plumber diagnosed it as copper central heating pipes having been attacked by the concrete in the hall floor screed, and rerouted the entire ground floor of the system via the first floor.
It never occurred to me to talk to my house insurers.
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