[Tanoc]

Open plan houses are the noisiest places to be. And for some reason the same people who like open plan houses also hate carpet and love high ceilings. Meaning you get the plate reverb effect on everything you do. How living in a place like that doesn't give you tinnitus I'll never know.

[Groxx]

The general strategy to avoid this is to have fabric walls and/or ceiling drapery. It cuts noise down to normal house levels, because yeah, if you leave everything bare it's just an echo chamber.

Loud sounds leak through still of course, but echoes and background clatter drops off extremely quickly. Particularly if you use two layers.