Noise dampening should be part of the health code or something.
I'm with you 100%. Let's focus on building high quality units that will actually last longer than 10 years. Sure, it'll drive up the rental prices, but hopefully people would move out of the cheap garbage everyone is used into nicer units with privacy. That would open up a lot of space in now less desirable units.
Health code would be a good start. Hell, create a new sound transmission standard & test that actually requires the range of frequencies you'll hear in an apartment (including subwoofers and doors slamming), and make landlords have to supply that information if requested. At least I could actually shop around for something better instead of rolling the dice on neighbors.
it's not expensive, either.
https://www.google.com/shopping/product/1727307288755176845?...
of course, I've never installed the stuff (I've heard stories, though) so I don't know what it does to labor costs.
Of course the cheapest thing of all is making a building out of concrete or masonry that can last for over a century and has inherently great noise dampening.
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The brackets are 'dry wall' but mandate the higher quality stuff that won't support mold growth.
Yes, there's an inner gap between the outer walls, and the floor/ceiling have a bit of extra padding of some structured engineering product that dampens vibrations.
The outer walls have studding to allow for cords and in-wall plumbing.
Do NOT run plumbing or put any shelving/fixtures on walls adjacent to another unit.
I haven't seen, or figured out my self, how to make the vertical noise isolation equally effective. I suspect a dedicated between floor crawlspace would be effective (but raise costs notably).
The core-wall approach CAN lower costs since it allows for a structural core with studs as dense as desired and no cut-outs.
1/2 layer of cork underneath the top layer of flooring is inexpensive and effective for noise isolation ...
Once I lived on the bottom apartment in a two storey apartment block. The floor boards were a nightmare and eventually we had to move. Upstairs footsteps across the floor were loud enough to wake us up, and I don't just mean squeaky boards, but just the thumping knocking sound resonation. Sometimes I could make out the words being said in their conversations. Never again.
In the concrete building, we could never hear neighbors above of below us, in the wood framed building, we could hear foot steps and even voices. Our upstairs neighbor had a squeaky bed and we could clearly hear the bed every time they were intimate.