waste pipe noise

[Newby2]

I had a new upstairs bathroom fitted recently. Now every time (especially in the early morning) after I use the washing basin tap in the bathroom, there is a knocking noise every 20 seconds or so from the sink waste pipe (inside the wall), lasting for about a few minutes. It seems it does not matter if I use the hot or cold tap.

What could be the cause of this and how to get rid it? Is it because of air trapped in there?

Any tip much appreciated!

 

[Newby2]

test

 

[Rico99]

Hi there,

How is the water supplied to your basin, mains or from a tank in the loft.

If from tank in the loft, then check out the ball valve in your cold water tank, washer maybe on the way out making it vibrate when refilling.

If all is mains pressure then could jumper in tap if traditional style taps or pipes not clipped properly.

Rico

 

[Nige F]

good point ...it might not be the waste. To Test pour water from another container down basin Having drawn the water previously.