Tenant in basement apartment (legal unit) complained of unusually high noise and unusually high vibration activities some nights.

The only issue with the single units doing both jobs is that they spin very fast and cause a lot of vibration if the floor is not sturdy. 8) A duplex up 3/2 or 4/2 could be really nice for LTR, MTR, or STR.

@Geritt ShipleyThere is acoustical insulation and sound rated drywall - just recognize it is not cheapAlso once you get the sound issue resolved next will be the vibration which also creates sound and to alleviate that is done through isolation hangers for the drywall.

Scott, this is only an opinion because I have not replaced an existing pipe, but for the new pipe that I had to have done, there were some specific requirements that had to be met in order to tie in to the water companies pipe.Therefore, I would ask most of these questions directly to the water company involved to see if there are any specific things they will look for before they allow the water into your pipeline.I would not lay the new pipe over any existing pipe because of the possiblity of water pressure vibrations could accidentally vibrate the new pipe against some sharp part of the detoriating old pipe causing a eventual break in the new pipe.

If it's vibrations like foot fall, then it won't help at all.

Or a super thin shells that vibrate whenever the compressor kicks in.) 

A real structure will have some vibration dispersing but not moving 2 to 3 feet back and forth one each kick.

@James Sestito Generally if you have to ask how close is too close, then it is;-)I was in a friend's income property in Quincy, right next to the commuter line and while it was not that loud, there was vibration.

With the cop we found drug parafanalia and a vibrating ****** in a box (I didn't even know such a thing existed) sitting on the coffee table and a TV with the series number scraped off in an empty bedroom.

Excessive noise can violate a tenants right to enjoyment here is the new York lawExcessive noise and vibrations violate a New York State law known as the “warranty of habitability.”