Looking for Less Invasive Solutions for 1-Hour Fire Rating + 50 STC in Floor/Ceiling Assemblies

[hallro]

Does anyone know of products or systems that can achieve both a 1-hour fire rating and a 50 STC & IIC for a floor/ceiling assembly?

We’ve previously always added an extra layer of plywood to the floor, but this requires vacating tenants from above, which is disruptive. We've also considered drop-ceiling assemblies like UL L581.

Have you come across any less invasive solutions or manufacturer products that meet these requirements? Any recommendations or insights would be greatly appreciated!


Scope: Converting garages below an existing multifamily development into ADUs.

 

[Jay Smith]

I don’t know how much the double plywood matters in this attached design, but it might be worth asking Pliteq about it.

 

[steveray]

If there are already tenants above, why are you messing with the rating now?

 

[Yankee Chronicler]

Does anyone know of products or systems that can achieve both a 1-hour fire rating and a 50 STC & IIC for a floor/ceiling assembly?

We’ve previously always added an extra layer of plywood to the floor, but this requires vacating tenants from above, which is disruptive. We've also considered drop-ceiling assemblies like UL L581.

What's the existing construction? A floor-ceiling assembly is a complete assembly. How can we suggest anything if you haven't told us what the starting point is?

 

[bill1952]

Residential building, and for whatever reason garage is not separated from 1st floor dwelling unit. Now to put an ADU in this space you need and hour separation and would rather not disturb tenants
in first floor unit. It seems the UL L581 works. Are you just looking for less expensive that gets the 1 HR and STC as well as doesn't disturb tenants?