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Firewall related

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VERMA071

Member
Joined
Apr 24, 2014
Messages
22
Location
new jersey, usa
Hello Everyone,
I am trying to learn to code and have a very basic question related to IBC Table 506.2. I will take most restricted assembly A2 as my occupancy. As per table for A2 Occupancy and single story sprinkled building, Maximum permissible area is 38,000sf. If I use area modification formula (frontage increase only not sprinkler) I will get final area more than 38,000sf. My question is :
Do we need firewall after 38,000sf or not? How does it work?
Please advice.
Thx,
 
cda said:
Good resource

My answer change type of construction, add a two hour wall which makes another building, there are a few choices

http://www.specsandcodes.com/articles/default.html


http://www.specsandcodes.com/articles/code_corner/The Code Corner No. 16 - Allowable Building Area Part 1.pdf
Click to expand...


Thanks for your quick reply and the links you posted. I will definitely go through them.
If the current construction type is IIIB, then I assume as per your answer that I will have to break the space so that it does not go more than 38,000sf.
Am I right?
thanks
 
I am not real versed in the many ways to do an increase.
Give it today and tomorrow for better replies


How about Type III A?? You go to 56000 with that
 
If you want to stay as Type IIIB construction without a sprinkler, then, yes, you will need a fire wall to go larger per story. If you want more area without a fire wall, you can go up and/or down. You're allowed up to two stories at 38,000 sf each and a basement of up to 38,000 sf. However, if you want a single story to exceed the 38,000 sf, then a fire wall is necessary (or, as cda suggested, go to another construction type that allows more area, or add a sprinkler system). You may be required to add a sprinkler system anyway because of your Group A-2, especially if the fire area exceeds 5,000 sf and/or the occupant load is greater than 100.
 
RLGA said:
If you want to stay as Type IIIB construction without a sprinkler, then, yes, you will need a fire wall to go larger per story. If you want more area without a fire wall, you can go up and/or down. You're allowed up to two stories at 38,000 sf each and a basement of up to 38,000 sf. However, if you want a single story to exceed the 38,000 sf, then a fire wall is necessary (or, as cda suggested, go to another construction type that allows more area, or add a sprinkler system). You may be required to add a sprinkler system anyway because of your Group A-2, especially if the fire area exceeds 5,000 sf and/or the occupant load is greater than 100.
Click to expand...

First I would like to thank you for replying.
So If I keep the building single story with a sprinkler system and IIIB construction type, I can go more than 38,000sf without adding a fire wall. Am I getting right or missing something?
 
RLGA said:
If you want to stay as Type IIIB construction without a sprinkler, then, yes, you will need a fire wall to go larger per story. If you want more area without a fire wall, you can go up and/or down. You're allowed up to two stories at 38,000 sf each and a basement of up to 38,000 sf. However, if you want a single story to exceed the 38,000 sf, then a fire wall is necessary (or, as cda suggested, go to another construction type that allows more area, or add a sprinkler system). You may be required to add a sprinkler system anyway because of your Group A-2, especially if the fire area exceeds 5,000 sf and/or the occupant load is greater than 100.
Click to expand...


More than likely a sprinkler system is required
Does he still get the allowance to go bigger?
 
VERMA071 said:
First I would like to thank you for replying.
So If I keep the building single story with a sprinkler system and IIIB construction type, I can go more than 38,000sf without adding a fire wall. Am I getting right or missing something?
Click to expand...
Yes. With a sprinkler system, a single story building can be four times the tabular allowable area, plus the added area for frontage increase. If the building is sprinklered with multiple stories, then the allowable area is permitted to be three times the tabular allowable area, plus the added are for frontage increase. In the 2015 IBC, the tabular allowable area is already calculated if a sprinkler is installed throughout, all you have to do is the calculation for frontage increase.

I should point out that the allowable area is per story up to three stories. So if your building is taller than 3 stories, the total building area cannot be more than three times the allowable area per story, and any single story cannot be more than what is permitted per story.
 
Last edited:
cda said:
More than likely a sprinkler system is required
Does he still get the allowance to go bigger?
Click to expand...
Yes. There is no limitation to using the increase for allowable area if the sprinkler is required by another code provision.
 
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