Allowable stories & area for existing building with new occupancy & non-separated mixed use

[ScottB]

Greetings, I need clarification regarding allowable stories and area. The code used is the 2019 California Building Code.

We are doing a tenant improvement to an existing 12,200 sq.ft. 2 story Type V-B unsprinklered non-separated mixed use building. The occupancy groups will be A-2, M and B. I understand that the most restrictive occupancy will be A-2 and further that we will at least need to add fire sprinklers. Checking Table 506.2 for area, A-2 SM without height increase allows 18,000 sq. ft. Table 504.4 for stories, A-2 S without area increase allows 2 stories. The building basically has 100 feet or more on three sides and 50 feet on one side. It appears that we fall within the allowable area and height shown in those tables for A-2 occupancy.

However when using the UpCodes calculator, one data input asks "Does your plan incorporate the sprinklered height increase or the area increase from Tables 504.3, 504.4, and 506.2?" None is not a selection option so I have to enter one of the choices. Either choice returns that the building is not compliant, either too large or too many stories.

What am I missing? What do I need to do to make the existing building be code compliant based on the information listed above?
Thank you for any advice.

 

[MtnArch]

You could also check Ara Sargsyan's CHA-CHA calculator (https://ara4help.com/).

 

[mtlogcabin]

Did CA adopt a version of the existing building code and if they did will section 1105 help.


1011.5.2 Height and area for change to an equal or lesser-hazard category.
Where a change of occupancy classification is made to an equal or lesser-hazard category as shown in Table 1011.5, the height and area of the existing building shall be deemed acceptable.

 

[ScottB]

Thank you for your responses. I learned that in CA, any A occupancy may only take the height OR area increase baked into the tables of the 2018 IBC, the only way to get 18,000 sq. ft. for an A-2 is to limit not use the value which is associated with the height increase (stories = 2 instead of 1). This only applies in California. Any other state, you could use the 18,000 number WITH 2 stories. See CBC Table 506.2. I was able to get the building to work using occupancy fire separation per Section 508.4. Thanks again.