Scenario: I'm the owner of a multi-unit 2 story apartment, I'm the owner. PeopleThe people living up and down are cousins to each other and are in the process of switching aptsapartments -- long story, don't ask. UppersThe upstairs tenants have areadyalready moved down but downersthe downstairs tenants have yet to move up, so the top is vacant for a few more weeks.
Lower unitThe lower unit's kitchen has nice vinyl tile that's easy to clean, that the tenants like and are used to, while upperthe upper's kitchen has commercial very low-pile carpet which helps with sound. Kids running around make reducing any low-end sound a priority. LowerThe lower unit people have requested similar tile for the upstairs for easy cleaning, but I don't want to get rid of carpet for the aforesaid reason.
SoundThe sound on the high end of the scale between units is not a current problem, it's the footsteps/running thuds I would want to keep minimized, which no doubt may be higher with just tile over pine. RestThe rest of the unit will remain carpeted.
TongueThere is tongue & groove pine is below the carpet. There's very little "give" on the carpet. Can I sandwich the carpet in with quarter-inch subfloor, screwed down well, topped with vinyl? (This is the part where you say yes, ha.)
I may use no-glue tile or tile squares with silicone adhesive. I'm not concerned about absolute perfection in performance/looks for this. If it's not okOK to sandwich the carpet, I don't want to put down expensive soundproofing stuff and would tell the tenant to live with carpet.
Seems the only reason not to sandwich would be if a future 300lb'er would jump around cracking the subfloor, but they are all small people.