UK Landlord Forum / Life

I don't know if anyone can help here as it's a bit of an odd question, and I'm not the landlord.

I'm a leaseholder living in ground-floor flat.  The leaseholder of the flat upstairs has rented their flat out (actually to some pretty unsavoury characters but I don't know any way out of that). 

The plumbing for the upstairs flat is knocking really badly, and I've asked the landlord to get a plumber as I am worried the air trapped in the pipes will loosen the joints and cause a(nother) leak into my flat.

This is the odd bit.  The landlord is so far ignoring my requests because the tenant is insisting it's me banging on the pipes that's making the noise. The landlord for reasons of their own is accepting that.  We have been through this before, two years ago with the same people, with him complaining to everyone that I'm banging on his pipes. (I tried to explain that it was just air trapped and moving in the pipework.  I even said he could just google it, but just got a mouthful of abuse for my trouble).  Eventually we got a leak from their washing machine connector, which they initially denied came from their flat (they said it must be from mine, even though all our pipes are at ground level).  They did then fix it but it did stain our kitchen ceiling, which didn't cost anything to fix as we had paint anyway.

I'm really concerned in case get another leak which might not be so easy to sort out and will be more costly.

My question is, does their landlord's refusal to try and deal with the water hammer now mean they'll be liable if it results in loosened joints and damaging leaks?  The construction upstairs is floorboards laid over concrete sections, so we have absolutely no access to their pipework to lag or secure any of it.

Any info would be gratefully received, thanks.

You appear to be asking who is (will be) liable for a leak that has not [yet] happened?