Fire separation wall between tenants in warehouse

[Sdpaddler50]

Hi, I have a project in So-Cal where my client will be occupying about 250K sq ft, of an existing, 500K sq ft bldg. There is already a tenant in there, with mostly storage (S) and some offices (B). My client will have the same occupancy, mostly storage, and some small offices (S/B). Per the Cal Bldg Code (CBC) Table 508.4, no separation is needed between these two occupancy groups. But, in cases like this, i have normally had min. 1 hr walls between two separate companies, under the same roof. If anyone out there is using the CBC/CFC, can you tell me if a 1 hour wall is needed? it makes sense, but looking for a code justification. Thanks.

 

[stookeyfpe]

It's not required under the 2010 CBC (based on the 2009 IBC), Table 508.4. Separation is required by Table 509 for certain incidental uses, regardless if the building is protected by an automatic sprinkler system.

Under the CFC, one-hour fire-resistive barriers could by required under Chapter 23 to separate high-hazard commodities from Class I-IV commodities

 

[Sdpaddler50]

Stookeyfpe, thank you for your response. Since S-2 is low hazard, and S-1 is moderate hazard, i then started wondering why a higher degree of fire separation be needed between a B/S-2. IE, no sep between B/S-1, but 1 hr for B/S-2 with sprinklers?

Then i searched this site, and found the following thread from you, to someone else asking the same exact question: "Actually, look at the other way. Say you have a warehouse filled with bags of ice (Group S-2) and adjacent to it is a Group B occupancy with modular furniture offices, server rooms and the like. The Group B occupancy presents a bigger fuel load than the S-2 so the IBC requires fire-resistive separation to prevent fire extension into the less hazardous area." I can't say i completely understand the logic on this, but at least i have a clue on how the code folks were thinking.