Can you get water hammer when stopcock is off?

[Robcrick88]

Been getting water hammer everytime neighbour turns off their taps. Very loud in our house and have asked neighbour who denies hearing anything. I tried turning off my stopcock and switching off boiler for a few hours and could still hear the banging when they use their taps. Is it possible to get water hammer with my stopcock off? It's driving me mad as I can not locate where the bang is coming from. We never had the problem until a few days ago and the only thing I thought it could be was Thames water turned the mains off for half hour a few weeks ago. We live in a row of 8 terraced houses on a shared main.

 

[Deleted member 120897]

If it’s from your neighbour, turning off your stopcock won’t solve the issue. Also if the incoming pipe is copper, then the sound can travel.

 

[Robcrick88]

Also

So would the problem be with them having water hammer and the sound travelling back to my pipes? Don't get any noises when we use our taps or even washing machine. They aren't acknowledging they can hear anything and the sound in my house is very noticeable. My idea of turning off stopcock was to find out if the problem was mine or them.

 

[John.g]

May be install a mechanical type shock arrestor (Pegler or Caleffi) as close to your stopcock as possible which just might stop the neighbour's water hammer (and yours), certainly worth a try especially if you can self install.

 

[ShaunCorbs]

Correct looks like it’s not yours / you can’t do anything

 

[Robcrick88]

Correct looks like it’s not yours / you can’t do anything

Could it be my stop valve even though its fairly new? Possibly due to Thames water increasing water pressure. I can hear the bang when neither of us is running water and can hear it when my wife is in the shower and they turn on and off their tap next door. It's driving me mad as I have limited access to my pipework without causing some damage and If its not my pipes would be a pointless task. Is there a way to prove its definitely them on a shared mains.

 

[John.g]

Are you on the very end of the 8 terraced housing or someway along?, what about the neighbour on the the other side of you, if there is one?.

 

[ShaunCorbs]

No as it still happens when you turn yours off

 

[Robcrick88]

Are you on the very end of the 8 terraced housing or someway along?, what about the neighbour on the the other side of you, if there is one?.

Were 4 along and neighbour 3 hears nothing he said and we don't hear their water at all. Neighbour 5 is the problem but their saying not noticed anything either but given how loud the noise is sometimes when they turn their tap off I can't see how they can't have noticed.

 

[Robcrick88]

Were 4 along and neighbour 3 hears nothing he said and we don't hear their water at all. Neighbour 5 is the problem but their saying not noticed anything either but given how loud the noise is sometimes when they turn their tap off I can't see how they can't have noticed.

We had water hammer when kitchen was first done 2 years ago when upstairs toilet and tap was used but turned down the isolation valve to reduce flow to the toilet and sink and this has worked well and still working at not getting the hammer noise when we use them.

 

[John.g]

Well, you could install a arrestor somewhere convenient there, I would get one (maybe they are all like this) where you can set the air end pressure before installation to 0.25 to 0.5 bar lower than the mains pressure, you can buy a pressure gauge that attaches to a tap to measure the static head.

 

[Roy_66]

So would the problem be with them having water hammer and the sound travelling back to my pipes? Don't get any noises when we use our taps or even washing machine. They aren't acknowledging they can hear anything and the sound in my house is very noticeable. My idea of turning off stopcock was to find out if the problem was mine or them.

Just a stupid question: When you turn off, is the water really off - go to highest tap and see if it still flows.

Note for taps with washers the washer can come loose from the jumper and give you hammer, particularly if the tap is overtightened when shut which pancakes the washer so central hole nolonger tight fit. It will then do lots of strange things. So one other silly question: do you use your stop tap a lot?

Other thing - have you a header tank or w/c with a bouncing ball/ float valve? Perhaps action of a neighbour could set them off.

Perhaps you can get neighbour to find an action that sets off your noise then trace it.

I'd get a professional in if you are stuck.

Cheers,

Roy (amateur)

 

[Robcrick88]

Just a stupid question: When you turn off, is the water really off - go to highest tap and see if it still flows.

Note for taps with washers the washer can come loose from the jumper and give you hammer, particularly if the tap is overtightened when shut which pancakes the washer so central hole nolonger tight fit. It will then do lots of strange things. So one other silly question: do you use your stop tap a lot?

Other thing - have you a header tank or w/c with a bouncing ball/ float valve? Perhaps action of a neighbour could set them off.

Perhaps you can get neighbour to find an action that sets off your noise then trace it.

I'd get a professional in if you are stuck.

Just a stupid question: When you turn off, is the water really off - go to highest tap and see if it still flows.

Note for taps with washers the washer can come loose from the jumper and give you hammer, particularly if the tap is overtightened when shut which pancakes the washer so central hole nolonger tight fit. It will then do lots of strange things. So one other silly question: do you use your stop tap a lot?

Other thing - have you a header tank or w/c with a bouncing ball/ float valve? Perhaps action of a neighbour could set them off.

Perhaps you can get neighbour to find an action that sets off your noise then trace it.

I'd get a professional in if you are stuck.

Cheers,

Roy (amateur)

No tank in loft and toilet doesn't have a ball valve. stopcock definitely stops all water flow and have checked pressure with pressure meter and getting 3 bar. When neighbours are out and in night we get no water hammer at all. As soon as neighbour uses their taps we get the noise. The only thing I can be is the sound of their water hammer travelling back to my pipe causing the loud bang. We even hear it when our water is running occasionally.

 

[John.g]

have you noted the pressure gauge pressure changes while water hammer taking place?.