Thickening party wall under floor level

[Ljc1980]

I live in a semi detached and ive been getting irritated recently by a clunking noise coming from neighbours pipes, sounds like probably water hammer every time they run kitchen tap.

The neighbours house is about a meter or two lower then mine so a large part of the dividing wall is under our suspended floor.

If I was to add an additional concrete block skin to the party wall under our floor do you think this would have any effect on dampening the annoying noise?

They wall under there looks pretty poorly pointed, with a few gaps in the mortar so I thought this might have a bit of a benefit?!

I've attached sketch as quite hard to explain.

 

[jacko555]

Or explain and offer to pay/fit water hammer arrestor?

 

[^woody^]

Probably no perceived benefits for the effort and cost.