Neighbours taps slam my pipes

[P B]

Every time the neighbours use their water it vibrates and visibly shakes mine causing a slam when they shut off .
Shared mains with separate internal stopcock .
Is this usual?
Any solution to prevent this?
Driving me potty
Thanks

 

[Scott_D]

has it just started?

 

[P B]

has it just started?

Hi scott_d,
No but since I've had boiler replaced and took out old remains of galvanised mains feed it had become very noticable. Old galvanised was so coroded that it possibly dampened the force. It was also very heavy.
I've reduced my flow by turning my stopcock nearly off...
The plumber who replaced has only layed pipes in existing notches with no clips etc.
External stopcock serves 4 semi detached houses. Mine is one end of four.
Thanks

 

[Scott_D]

Shutting the stop tap reduces flow not pressure

Cut out any dead legs that can trap air
Clip pipes
Pressure reducing valve
Shock arrestor

 

[P B]

Shutting the stop tap reduces flow not pressure

Cut out any dead legs that can trap air
Clip pipes
Pressure reducing valve
Shock arrestor

Thanks though is this common problem between houses and should neighbours affect my pipes this much? Can i get them to do something ( in theory as they may not want to...)?
Cheers

 

[Harvest Fields]

Is it a combi boiler? Did you previously have a hot water cylinder in the airing cupboard?

 

[Ric2013]

Exact same thing in my house. Shared supply and the neighbour tees off before mine.

You aren't my neighbour are you?

Problem is most likely that our pipes aren't clipped properly and shake about as the pressure changes. Getting more likely to happen these days with modern solonoid valves in washing machines and quarter turn taps leading to water hammer as the flow is abruptly stopped, so the old ways of sitting pipes unclipped in notches which worked well for decades is now leading to noise.

I can't see how you can force the neighbour to do anything as the noise is essentially down to your pipes being able to rattle about.

Question to others: would it be useful to fit a shock arrestor as close to the source of the water hammer e.g. tap as possible (in the neighbour's house if the neighbour would allow this)?

 

[P B]

Exact same thing in my house. Shared supply and the neighbour tees off before mine.

You aren't my neighbour are you?

Problem is most likely that our pipes aren't clipped properly and shake about as the pressure changes. Getting more likely to happen these days with modern solonoid valves in washing machines and quarter turn taps leading to water hammer as the flow is abruptly stopped, so the old ways of sitting pipes unclipped in notches which worked well for decades is now leading to noise.

I can't see how you can force the neighbour to do anything as the noise is essentially down to your pipes being able to rattle about.

Question to others: would it be useful to fit a shock arrestor as close to the source of the water hammer e.g. tap as possible (in the neighbour's house if the neighbour would allow this)?

Hi,
If i am your neighbour then can you stop using your taps please
Closest point to neighbours will ne just above my internal stopcock...?

 

[P B]

Is it a combi boiler? Did you previously have a hot water cylinder in the airing cupboard?

Yes and yes. Although i always heard a noise when neighbours used cold but was more through the wall noise of thier pipes, not mine.
I can now hear flow from thier taps as a precursor to the bang!
Seem to turn on and off a lot ( worse when thier 4 children are in too)...

 

[Harvest Fields]

I would hazard a guess and say it is probably when they use their toilets. I would also guess that when your old boiler was stripped out and the new one put in, the pipework wasn’t cut out properly and lots of dogs legs have been left and just capped rather than removed. (But im just guessing).

 

[P B]

I would hazard a guess and say it is probably when they use their toilets. I would also guess that when your old boiler was stripped out and the new one put in, the pipework wasn’t cut out properly and lots of dogs legs have been left and just capped rather than removed. (But im just guessing).

Think its also the quarter turn taps type as flow and then slam is too quick for toilet - unless they have a toilet from a jumbo jet, cause thats about its speed from flush to slam. :-D
Nothing left in re old dog legs. No clips anywhere but up walls.
May have pic somewhere of landing feeds to a "T" where pipes move most. See attached. Ive circled the cold main showing up arrow points to 4m straight pipe which then drops 2.4 m to my stopcock then into original lead pipe into concrete floor.

 

[Harvest Fields]

New toilet inlet valves can slam shut. Depends on which one is fitted.

 

[Ric2013]

New toilet inlet valves can slam shut. Depends on which one is fitted.

I think most of the modern ones do.

 

[Ric2013]

Combi boiler will not help. Now all your water pipes are on mains pressure running through the boiler, so any pressure surge from the mains supply will affect your hot pipes too, to some degree.

Your floor joists are FAR too substantial for you to be my neighbour: mine are only 6.25 x 1.5" ! Although I note the same 'notch out half the joist' technique has been used (joist notches should not be more than 1/8 the height of the joist).

 

[Harvest Fields]

Combi boiler will not help. Now all your water pipes are on mains pressure running through the boiler, so any pressure surge from the mains supply will affect your hot pipes too, to some degree.

Your floor joists are FAR too substantial for you to be my neighbour: mine are only 6.25 x 1.5" ! Although I note the same 'notch out half the joist' technique has been used (joist notches should not be more than 1/8 the height of the joist).

1/8 the depth I’ve seen some sites in the few years I have been doing this.

 

[P B]

Combi boiler will not help. Now all your water pipes are on mains pressure running through the boiler, so any pressure surge from the mains supply will affect your hot pipes too, to some degree.

Your floor joists are FAR too substantial for you to be my neighbour: mine are only 6.25 x 1.5" ! Although I note the same 'notch out half the joist' technique has been used (joist notches should not be more than 1/8 the height of the joist).

Yes a complete hack out job so may just as well be 3.5" deep all the way :-0. luckily the timber pre 1950 was a lot better than the matchstick stuff i've been using upstairs.

 

[P B]

Combi boiler will not help. Now all your water pipes are on mains pressure running through the boiler, so any pressure surge from the mains supply will affect your hot pipes too, to some degree.

So any of the other houses use water and mine are going to bang? :-( Surely this isn't normal?
I have reduced the flow on my side and get far less noise when i use just my taps.
...Maybe i could ask neighbor to "TURN IT DOWN!" a little.

 

[P B]

So, as most of the floor boards are still accessible and not fixed back down again yet, should I take the opportunity to strap as many of the accessible pipes down now.
Unfortunately the plumber has left some of the pipes dangling mid joists and on cables completely unsupported and this may make strapping or clipping these ones a little harder full stop see additional picture .

 

[Ric2013]

It's not 'normal', but then shared supplies aren't the norm these days. I'm used to the noises mine makes and don't usually notice it, though it can sometimes be useful to know when the neighbour is in or out.

In the days of Garston, Croyden, or Portsmouth ballcocks, and taps to BS1010 the shutoff was gradual and so water hammer was less likely. As an experiment, you can probably open your stopcock fully and you'll be fine as long as long as you turn taps on and off slowly.

On a modern supply pipe feeding one dwelling, any water hammer (pressure transients) are removed by a substantial length of pipe from the next dwelling and connect back to a wider bore pipe in the street. As you presumably have a single 1/2" bore pipe supplying two dwellings, any water hammer hasn't got far to go before it can cause a nuisance and the narrow bore means the water is travelling at speed down the entire pipe length.

To be honest, that wiring is a snake's wedding: I have seen PVC cable cores push right through the insulation when in contact with a hot pipe, so I hope it is kept away from hot pipes! Also, 15mm pipe should be supported every 1.2m horizontally (about 4') so that isn't the greatest plumbing job either. It is also considered good practice to keep a 25mm clearance between electrical cable and any pipework. The proper way to support it in that location would be Munsen rings, or you can use plastic clips on a very long screw with a pipe offcut over the screw to give a decent length. Thinking alternatively, you might even be able to suspend it with some loops of cloth (old pair of jeans could be cut up) held by screws and washers to the joist on each side of the pipe. But sitting on cables is not an option.

 

[P B]

It's not 'normal', but then shared supplies aren't the norm these days. I'm used to the noises mine makes and don't usually notice it, though it can sometimes be useful to know when the neighbour is in or out.

In the days of Garston, Croyden, or Portsmouth ballcocks, and taps to BS1010 the shutoff was gradual and so water hammer was less likely. As an experiment, you can probably open your stopcock fully and you'll be fine as long as long as you turn taps on and off slowly.

On a modern supply pipe feeding one dwelling, any water hammer (pressure transients) are removed by a substantial length of pipe from the next dwelling and connect back to a wider bore pipe in the street. As you presumably have a single 1/2" bore pipe supplying two dwellings, any water hammer hasn't got far to go before it can cause a nuisance and the narrow bore means the water is travelling at speed down the entire pipe length.

To be honest, that wiring is a snake's wedding: I have seen PVC cable cores push right through the insulation when in contact with a hot pipe, so I hope it is kept away from hot pipes! Also, 15mm pipe should be supported every 1.2m horizontally (about 4') so that isn't the greatest plumbing job either. It is also considered good practice to keep a 25mm clearance between electrical cable and any pipework. The proper way to support it in that location would be Munsen rings, or you can use plastic clips on a very long screw with a pipe offcut over the screw to give a decent length. Thinking alternatively, you might even be able to suspend it with some loops of cloth (old pair of jeans could be cut up) held by screws and washers to the joist on each side of the pipe. But sitting on cables is not an option.

Thanks. Pipe will be moved above cables as there are even some cables over the top at some place. Very disappointed at sloppiness of install. Will need to cut pipe to do so as the cables will not be removed from CU. so I may as well move it to the joist to the right or left .
Incidentally all these cables and main fuse board , sit directly below the bath... Hope the new bath doesn't leak :-/

 

[firemant]

Do you have a water meter?

 

[Ric2013]

Do you have a water meter?

If he does...?

 

[P B]

Do you have a water meter?

No i don't. Why, is that likely to causeba problem too?
Thanks

 

[skoronesa]

I would try putting a small expansion tank on a tee right where the water line comes in. It will act as a big shock arrestor. When you secure your pipesuse something with a rubber insert. I don't know what you have available but I would suggest short pieces of insulation with a larger pipe clip around it. This way the foam insulation acts as a vibration dampener.

If you can get some polyethylene water line you could make a loop at the main, this may help with vibration as well.

 

[P B]

I would try putting a small expansion tank on a tee right where the water line comes in. It will act as a big shock arrestor. When you secure your pipesuse something with a rubber insert. I don't know what you have available but I would suggest short pieces of insulation with a larger pipe clip around it. This way the foam insulation acts as a vibration dampener.

If you can get some polyethylene water line you could make a loop at the main, this may help with vibration as well.

Thanks, was looking at this currently. Was about to use a few saddle clamps on the straight run first and see if that helps.