said by jack b:
I would think there would be a building requirement for a cinderblock firewall between adjoining living space, separating the units. This does not appear to be the case based on your photo, especially considering the fact you can easily hear "conversation" and whatnot from the other side.
If the builder is simply shrugging it off, I would call the city building inspector to get an opinion.
Check with local authorities on firewall specifications.
In highrises where I have worked, built in the 1970s, the units had two layers of 5/8 sheetrock on the metal studwalls separating them from the adjacent units. So that's four sheets of 5/8 sheetrock, 2.5 inches, plus an insulated stud cavity between units. However there were receptacles and phone jacks in these walls, albeit in metal boxes, but not caulked or sealed. I believe now such receptacles in firewalls must be firestopped, firecaulked, whatever. But requirements for low-rise buildings are probably less stringent.
Also I'm curious whether the neighbor's return air would be directly on the other side of the wall that says "PAN", or in adjacent stud cavities in the same linear plane. If it's in the adjacent cavities, that means you have 64 linear inches of studwall that are not sound insulated. What is the wall that says "PAN" made of?--
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