Area Separation Walls

[steveray]

Trying to start this as far as where the real rating is, whare penetrations are allowed and how they need to be protected.....

Q&A: Area Separation Wall Design

All of your area wall separation questions answered.

www.ul.com

Q: Are these wall assemblies rated for fire exposure from either side?

A: The UL Designs covering these wall assemblies typically include two configurations; a symmetrical configuration and a non-symmetrical configuration. When constructed in the non-symmetrical configuration, the assembly is rated for fire exposure from the area separation wall side only. Should a fire develop on the area separation wall side, the area separation wall resists the passage of fire while the protected wall provides the structural integrity and an additional level of resistance to heat transfer. When constructed in the symmetrical configuration, the wall assembly is rated for fire exposure from either side. Should a fire develop on either side, the protected wall, being non-rated, will fail leaving the area separation wall exposed. The combination of the area separation wall and the protected wall on the opposite side will meet the requirements for a 2 hour fire-resistance rating.

 

[Wstubbs]

I've been working on townhomes with the 347 firewall
penetrations are not allowed
the real rating is in the whole shabang

do you mean something else as to where the real rating is? it's a two hour isnt it?

 

[steveray]

I've been working on townhomes with the 347 firewall
penetrations are not allowed
the real rating is in the whole shabang

do you mean something else as to where the real rating is? it's a two hour isnt it?

In the full listing they (UL) show it tested from each side without the facing/ protected wall on the exposed side, the USG book alludes to the facing walls not being required as part of the rating at all....The UL Q&A seems to indicate that you need at least one facing wall to achieve the rating...If that is the case in a bearing wall situation, how is anyone rating the penetrations as I don't believe there is an actual listing....