Residential vs Commercial fire separation distance

[phillier937]

I'm in Ohio referencing OBC 2017 and RCO 2019

I have a multiple condo project. They are separating by 2 hr walls. They want to use 310.5.5 Multi-Family Alternative Compliance - which appears to apply.

In this case does the property fire separation distance from the Commercial Building Code 10' for VB construction (even though RCO doesn't call it VB) or do we use T 302.1 from the Residential Code that allow for 0 rated walls at 5'? It appears to be the latter since the RCO doesn't actually call it VB and there for 10' rule doesn't apply and we follow the 5' rule?

 

[Joe.B]

Don't know about Ohio codes, but here the Residential Code would not apply to multi-family projects.

 

[Builder Bob]

Usually the scope of the residential code applies to detached 1 &2 dwelling units or townhomes ------Our department also did not allow you to mix and match commercial codes and residential =such as using a fire wall between four attached units to create two 1 &2 family dwellings on each side of the singular fire wall.