Moving Pipes Undersink

[Madrab]

Ah, I see what you mean. The only thing is I don't have any 15mm copper pipe, though, I suppose I could buy some. Would it make much of a difference if I were to replace the isolation valve with the tap, then just put the isolation valve further up after making a cut?

If you don't have spare pipe then no - no reason not to do that.

 

[gjw123]

If you don't have spare pipe then no - no reason not to do that.

Great! I managed to get it done (waste pipes) - thanks for all your help! I've attached some pictures. Only thing is, one of the pipes was a little too short and I only realised this when it had been cemented in (I've circled it on the picture). One other was at a slight downward angle.

The depth to push the pipe into the joints appears to be 30mm and I think I managed to get it in maybe 15mm. It's fully sealed and there are no leaks. I'm just wondering if this is going to cause any big issues in terms of blockages etc.

I think I've also possibly caused some water hammer... it appears to be coming from upstairs. I've tried turning off the mains water, draining the faucets and turning them back on (bottom floor first). However, that doesn't seem to he working. I've seen a water hammer arrestor may help.

Would you be able to guide me on where to install this?

 

[Madrab]

It's fully sealed and there are no leaks. I'm just wondering if this is going to cause any big issues in terms of blockages etc.

Unlikely - just keep good waste pipe maintenance - once a month run a basin full of boiling water with vinegar/bicarb/jeyes or similar down it to flush the pipework out.

I think I've also possibly caused some water hammer

Why do you think you caused that - what do you do to make the pipes upstairs knock? Making the alteration to the cold supply downstairs shouldn't have 'all of a sudden' created water hammer upstairs. Maybe the mains stop tap wasn't fully open and now it is, so increasing the flow?

 

[gjw123]

Unlikely - just keep good waste pipe maintenance - once a month run a basin full of boiling water with vinegar/bicarb/jeyes or similar down it to flush the pipework out.


Why do you think you caused that - what do you do to make the pipes upstairs knock? Making the alteration to the cold supply downstairs shouldn't have 'all of a sudden' created water hammer upstairs. Maybe the mains stop tap wasn't fully open and now it is, so increasing the flow?

I'm not entirely sure to be honest! I did notice that the inside of the waste pipes I replaced were really thick with congealed debris, so I imagine the water is going through there a lot more freely now.

As mentioned, I've tried turning off the mains water, draining the faucets and turning them back on (bottom floor first), but that hasn't worked.

In terms of a water hammer arrestor, would a good place to put this be on the cold water pipe where I am going to also put the tap?

 

[Madrab]

what do you do to make the pipes upstairs knock

Arrestors don't always work, Ideally the cause of the hydro shock needs to be found and then sort that. It won't really be anything to do with the upstairs taps having air, it's usually down to a valve that closes too quickly and that makes loose pipework rattle/knock.

 

[gjw123]

Arrestors don't always work, Ideally the cause of the hydro shock needs to be found and then sort that. It won't really be anything to do with the upstairs taps having air, it's usually down to a valve that closes too quickly and that makes loose pipework rattle/knock.

Ah okay, fair enough. The only thing I turned off was the mains water valve. Other than that, I simply replaced the waste pipes which were very full, so I'm not sure if subsequently having clear pipes have increased the water pressure a lot, perhaps?

In terms of the noise, it does particularly appear to be coming from the pipes upstairs in the cupboard with the tank (though, it doesn't appear to be coming from the tank). The pipes lead into the loft (pictures attached).

I've subsequently touched each of the pipes as the knock happens and the only one I feel any vibration in is marked with an arrow in the picture. The tap at the bottom of the pipe turns off the water for upstairs (doesn't appear to be for the whole house, which is downstairs).