Need help with banging pipe from next door

[Kev1888]

Needing some help.

moved house a month ago and could hear pipes banging all night, called a plumber and it was due to the water in my house being turned off it affected when the neighbour used there’s, there was water in our pipes so we didn’t notice the water was off, both of us could hear the banging pipes.

now when next door use their washing machine there is a noise like a dunt in the pipes, the plumber cut away spare pipes in our loft and installed a non return valve on both mines and the neighbours water pipe at the stopcock And said that would fix it but it hasn’t. I can still here the pipes dunt, any ideas what this could be? It doesn’t seem to affect the water pipes for the upstairs but definitely the washing machine, not sure about the kitchen tap though.

i can’t tell if the noise is coming from my pipes or next doors but it’s driving me insane and making me want to sell up.

 

[Ben-gee]

A washing machine shuts off very abruptly, this can cause a shock wave to reflect back along the pipework. If any of this is loose you will get noise, try adding extra clips.
The other solution that can help is to add a “shock arrrestor”, this is basically a mini expansion vessel and it absorbs the energy from the reflective shockwave, thus stopping it shaking the pipework when it comes up to a bend.