Humming changed to screeching pipes late at night

We have had a humming noise coming from our bathroom late at night and the only way we could get it to stop was to flush the toilet and for some reason the toilet would flush all night.

We called out a plumber and he replaced the nylon washers with rubber ones and fixed the water level in the toilet cistern but the noise has changed to a screeching/banging noise, a really loud banging noise. So he came out again and replaced the valves which were worn and eveything seemed to be okay and then I used the sink late at night and the cold tap made the banging noise again.

The noise in the taps seems to be directly related to the temperature outside. It has been really cold this year temperatures dropping to -5.

When our neighbour uses there taps downstairs the banging noise happens as well, they also replaced their bathroom this year and I was wondering if firstly; how do i fix the problem and are they contributing/is there something wrong with their pipes too?

I've read loads of things and think it is the water hammer or loose pipes but I just don't know anymore, we keep getting things checked and replaced and the problem is continuing.

gonna be a worn tap in the house which will cause hammer even if its not on. put your hand on all the taps in the house when its happening to feel for a bang my bets its the kitchen sink

Hopefully you have a mains stopcock.

Until the problem is sorted you can turn this off over night.

Tony

The banging happens when we use the bathroom sink. If we use the kitchen sink you hear the banging in the bathroom. When the flat downstairs use their bathroom sink it's our bathroom tap that bangs but i notice that most of the noise re the humming is coming from the toilet!

toilet could be making the noise cus it has an equalibrium ballvalve which would be affected by the hammer comming from another valve / tap elsewhere. once i had to change all the taps in a house before i traced the faulty one