Creating a 1-hr floor from an exiting floor without adding a layer above the joists.

[Ryan Schultz]

I need to create a 1hr floor between a new dwelling unit and an existing unit.

The existing floor is..

• tile/carpet
• 1/2 plywood sub floor
• 2x10 and 2x12 wood joists.

Want to do something like the following...

• http://productspec.ul.com/document.php?id=BXUV.L201
• http://productspec.ul.com/document.php?id=BXUV.L202

Question: Can I achieve this 1-hr rating without adding a new layer of anything above the existing 1/2 plywood subfloor?

From my reading of the UL assemblies above, it doesn't look like it. For L201 or L202, anyway.

Just wondering if I missing something.

Thanks, Ryan

 

[cda]

Calculate it per chap 7???

 

[RLGA]

Look at UL M537 or do the calculated method as mentioned above, but you may still have to add something on top for IIC sound transmission compliance. There is also UL L513, but it requires something on top which can help with compliance with the IIC requirement.

 

[Ryan Schultz]

I think http://productspec.ul.com/document.php?id=BXUV.M537 is the ticket.

I think we can achieve a 50 STC based on the following NRC report:
http://www.primaryacoustics.com/images/ir766.pdf

Thanks.

 

[RLGA]

STC is one thing--IIC is another. Carpeting will help in those areas, but for the tile, you'll need to add something under the tile to absorb impact noise.

 

[Ryan Schultz]

Right you are...