# Demising Walls to Roof



## Robert (Oct 15, 2016)

I am working on an existing bar in CA which is 2800 sq. ft, single story. The space is common to adjacent tenants and the demising walls stop several feet short of the roof structure in the attic (basically two of the attics communicate with each other). The building is Type VB construction to the best of my knowledge. At what point would we have to extend the demising walls up to the roof with proper fire rating if we are adding space to the building? I see on Table 503 (CBC) that if we were to add a second story in an A-2 occupancy, the building would have to be Type VA, and I believe trigger us to get those demising walls up to the ceiling. Our second story addition will be B occupancy and that occupancy allows Type VB construction, so not sure if that would trigger the demising walls in the rest of the bar to be extended. Thank you.


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## ICE (Oct 15, 2016)

Tenant separation?  Every TI that I have been involved with had one.


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## mark handler (Oct 16, 2016)

The bar may have originally classified as a "B" occupancy.  Changes were probably made,  with or without permits.
Check with the city and find out if a CoO was issued as a "B" or "A2".
Also find out from city, What code it was originally permitted under.

Separation required to the roof.


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## Robert (Oct 16, 2016)

Thank you. It is a historic bar dating to turn of the century and I believe was always a bar. I worked on a TI (different job) a few years back that AHJ not require the demising walls go all the way up to the roof (basically the attic common walls were not fire rated). I'm trying to find out what triggers that...square footage or occupancy or construction type.


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## mark handler (Oct 16, 2016)

Robert said:


> Thank you. It is a historic bar dating to turn of the century and I believe was always a bar. I worked on a TI (different job) a few years back that AHJ not require the demising walls go all the way up to the roof (basically the attic common walls were not fire rated). I'm trying to find out what triggers that...square footage or occupancy or construction type.


A bar can be a "B" or an "A2" based on number of occupants. 50 is a magical number.......


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## Robert (Oct 16, 2016)

Thank you. There was an addition...don't know when. Perhaps it was B before addition then the occ load increased with addition changing it to A. At that point I can see full height demising walls required as the adjacent spaces are B occupancies...odd they were not installed. If the ceiling and walls below the ceiling are rated, could the demising wall above the ceiling be ignored for separation?


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## steveray (Oct 17, 2016)

"Tenant" separation never required.....Use separation maybe....


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## mark handler (Oct 17, 2016)

steveray said:


> "Tenant" separation never required.....Use separation maybe....


Not true see 2012 IBC 402.4.2.1
Never use the term "never".


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## steveray (Oct 17, 2016)

Malls and apartments yes.....I just figured a "historic bar" was neither.....Those would be fire partitions and not necessarily to the roof deck. Demising wall is bad terminology that needs to be eliminated from the vernacular IMO


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