# 2019 CBC Table 506.2 concerns



## Derrick Carter (Feb 25, 2020)

I'm using Table 506.2 to establish my allowable area in the 2019 CBC for an A-1 occupancy.
In the 2016 CBC Table 506.2 - two multi story options:
SM (without *height* increase)
SM (with *height *increase)

In the 2019 CBC Table 506.2 - two multi story options
SM (without *area* increase)
SM (with *area* increase)

(There are no indicator symbols showing changes or deletions to the table)

This is a huge difference?
Example: A-1 occupancy - Single occupancy, multistory no height increase
(Equation 5-2)

w/ Frontage Increases
2016: 41250sf  (16500 table)
2019:19250 sf  (5500 table)

without Frontage Increases
2016: 41250 sf  (16500 table)
2019: 42250 sf  (16500 table)

Am I missing something here?
I was able to wrap my head around the 2016 trade off thinking. 
Please enlighten me.
-dc


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## RLGA (Feb 25, 2020)

This is a printing error. Late last year, I notified a friend of mine, who is on the California Building Standards Commission, about the error. I don't know if he's acted on it or not, but the online version still hasn't been updated and there is no errata posted on the BSC website yet.


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## Derrick Carter (Feb 26, 2020)

Thank you very much. I appreciate you taking the time to clarify this for me.


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## Builder Bob (Feb 26, 2020)

Just out of curiosity, is the second number 200% or 300% of the lowest number - 
For ease of discussion, i will use 5,000 SF at the tabular value
Non- Sprinkler - Lowest             5,000 SF
Sprinkler One story = 300 %      15,000 SF
Sprinkler multi-story = 200%       10,000 SF


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## RLGA (Feb 26, 2020)

Builder Bob said:


> Just out of curiosity, is the second number 200% or 300% of the lowest number -
> For ease of discussion, i will use 5,000 SF at the tabular value
> Non- Sprinkler - Lowest             5,000 SF
> Sprinkler One story = 300 %      15,000 SF
> Sprinkler multi-story = 200%       10,000 SF


The issue here is the particular requirements of the CBC and not the IBC. The CBC does not allow the use of a sprinkler system to increase both the area and the height--under the CBC, it is one or the other. The problem with the 2019 CBC is that in the area table (Table 506.2) they printed the two sprinklered multi-story areas with the descriptions of with and without "area increase" when it should have been with or without "height increase." 

If the 2019 CBC was printed correctly and a sprinkler is used for a height increase, then the allowable area for "SM (with height increase)" would be required--on the other hand, if the height increase is not used, then the allowable area for "SM (without height increase)" could be used. The misprint uses "area" instead of "height," which does not make sense.


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