How to turn existing wall into 2-hour rated wall?

[J La]

Doing an A-2 tenant improvement in an existing 1-story building that has 3 tenant spaces. Our A-2 space backs up against B and M tenant spaces. The building is Type V-B non-sprinklered and requires separated occupancies based on building square footage, so Table 508.4 says we need a 2-hour separation between the A-2 and these two other occupancies (2015 IBC).

The existing tenant demising walls appear to be wood-framed 2x4 with 1 layer of 5/8" GWB on each side. How can we convert the existing wall to a 2-hour rated partition from only one side, so that we don't have to do work in the adjacent tenant spaces? 722.6.1.1 only allows for calculated assemblies to a maximum of 1-hour, so we can't use that method.

 

[classicT]

Frame a new "double" wall, or use a shaft wall system.

 

[steveray]

Shaftwall....

 

[classicT]

 

[J La]

Thanks!

 

[classicT]

Thanks!

Absolutely... we hope that you'll stick around.

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[SCBO1]

J. La,

PROPRIETARY, has to be done the way the manufactures have designed and tested.

TyJ. has provided a Certain Teed Gypsum design from the Gypsum Association, there may be other ways and other designs

 

[Tim Mailloux]

Shaft wall is the simplest way.