# Occupant Load vs. Occupancy Group Classification



## el cholo (Jul 14, 2014)

Table 1004.1.1 Commentary says "establishes minimum occupant density based on the function or actual use of the space (not group classification).

Okay, so if I have a restaurant with an area where people can buy Chips & other products to go, that is Mercantile Area, maybe another area where products are stored, that can be Storage Area, what about the lobby & the restrooms, I'll count that as Business Area, etc…  But wait, assuming all of these spaces add up to more than 10% & thus not accessory spaces, isn’t this really a Mixed Occupancy now with all the fire separation requirements???

Just FYI, I found this website searching for Code interpretations on Google some time ago.


----------



## cda (Jul 14, 2014)

Welcome from northern tx wish I was at the beach


----------



## cda (Jul 14, 2014)

So what is your real question??

How to determine occupant load?

Is separation needed?

Wish they would cover more than one hour of building code in architect school


----------



## ADAguy (Jul 14, 2014)

Speaking for El Cholo, his question seems evident:

1. Is seperation of occupanicies required, given that the total of all seperate occupancies (uses?) by definition, when added together exceed 10% of gross space?


----------



## steveray (Jul 14, 2014)

Mixed uses, nonseparated, A2 most restrictive....


----------



## cda (Jul 14, 2014)

Yea but is the op getting the

Occupancy type correct to begin with


----------



## kilitact (Jul 18, 2014)

Mixed use. What's the square footage of the assembly, mercantile and storage areas? Could possibly be mixed use non-separated, if the space meets the code requirements for the most restrictive use  .


----------



## el cholo (Jul 20, 2014)

View attachment 2407

	

		
			
		

		
	
Ok, guys see attached drawing for reference (This is not the actual plan).  My questions are in *bold* lettering below. This restaurant will on the 1st floor of an existing parking garage, there are other restaurants, businesses even a day care in this same parking garage already.This is 2006 IBC...The Garage is 84,685 SF per floor, 6 Tiers, not-sprinklered, so assuming Construction Type IB (It's a precast concrete garage structure).  There is 2 HR wall separating Garage from all the tenants, due to Section 509.8 (This section doesn't include A occupancy though)The restaurant is 8,300 SF total.  Sprinklered per section 903.2.1.2,  Per Table 1004.1.1, I am dividing the restaurant spaces per actual use of space, not group classification.I get...1. Servery area at 1,300 SF gross counted as Mercantile per Table 1004.1.12. Dining area at 4,000 SF net counted as Assembly (unconcentrated) per Table 1004.1.13. Kitchen at 2,300 SF gross counted as Commercial Kitchen per Table 1004.1.14. Mechanical at 350 SF gross counted as Mech Equip per Table 1004.1.15. Restrooms/Corridors 350 SF counted as Business per Table 1004.1.1So because the servery area is 16% of the total, I cannot count the Mercantile area as an accessory space & thus I have to be a Mixed Occupancy...  Now the question becomes, *if I can have non-separated uses because I don't want a fire rated wall between the servery & dining spaces? * So, per section 509.8 the building doesn't include the garage, as that is separate & it's just a single story building of Type IB then.  The most restricted occupancy within the restaurant I have is A2, which is 11 stories, Unlimited Area.  So I'd be good with the non-separated uses here, except that section 507.3 says that because the building is Unlimited Area, A2 needs to be separated by 2 Hours from the Mercantile space that is within the restaurant!  *Is this right?**I am tempted to just call out the entire space as an A-2 & be done with it?*  But that means the max. occupant load sign the Fire Marshall will put up on the building will not be correct per Table 1004.1.1.Let me know if you need more info to help me out...

View attachment 1074


TI Restaurant Code Analysis 11x17.pdf

TI Restaurant Code Analysis 11x17.pdf


----------



## cda (Jul 20, 2014)

Will let someone else address the seperation question.

But the building official is going to set the occupant load, so if you have enough exit width , even if you call the whole thing an A what does it matter??

"""I am tempted to just call out the entire space as an A-2 & be done with it? But that means the max. occupant load sign the Fire Marshall will put up on the building will not be correct per Table 1004.1.1.""

Can you define what you mean by "servery"???

"""" Servery area at 1,300 SF gross counted as Mercantile per Table 1004.1.1"""


----------



## cda (Jul 20, 2014)

This is from 2009 not sure if it helps you

507.3.1 Mixed occupancy buildings with Groups A-1 and A-2. Group A-1 and A-2 occupancies of other than Type V construction shall be permitted within mixed occupancy buildings of unlimited area complying with Section 507.3, provided:

1. Group A-1 and A-2 occupancies are separated from other occupancies as required for separated occupancies in Section 508.4.4 with no reduction allowed in the fire-resistance rating of the separation based upon the installation of an automatic sprinkler system;

2. Each area of the portions of the building used for Group A-1 or A-2 occupancies shall not exceed the maximum allowable area permitted for such occupancies in Section 503.1; and

3. All exit doors from Group A-1 and A-2 occupancies shall discharge directly to the exterior of the building.

This section allows Group A-1 and A-2 occupancies in mixed occupancy, single-story unlimited area buildings under limited conditions. Atypical example of a practical application of this would be the construction of a strip mall that is mainly for retail stores, but might contain a restaurant or a movie theater, or both. Group A-1 or A-2 buildings would not be permitted as standalone unlimited area buildings. Similar to the requirement in Section 507.3 for Group A-4 buildings, unlimited area buildings that contain a Group A-1 or A-2 occupancy are not permitted to be built of Type V construction.

The restrictions on the use of Group A-1 or A-2 occupancies in mixed occupancy, unlimited area buildings include: (1) required separation; (2) limited area of each Group A occupancy to the area allowed in Section 503.1; and (3) all required exits discharging to the exterior.

Item 1 states that the Group A-1 or A-2 occupancy is required to be separated from the rest of the unlimited area building by fire barriers in accordance with Section 508.4.4. For example, if a strip mall contains mercantile facilities next to a theater (Group A-1), the theater would need to be separated from the mercantile facilities by a 2-hour fire barrier, as determined from Table 508.4. Although the unlimited area building is required to be sprinklered, the required fire-resistance rating for the Group A-1 or A-2 occupancy separation must be based on the nonsprinklered entry in Table 508.4 (i.e., no reduction is permitted in the fire-resistance rating of the separation due to the presence of the sprinkler system).

Item 2 requires each Group A-1 or A-2 area to be limited to that allowed by Section 503.1. For example, if the strip mall mentioned above were Type IIB construction, the allowable area of the theater would be 34,000 square feet (3159 m2) [tabular value of 8,500 square feet (790 m2) × 4]. Note that the allowable area is increased by 300 percent as permitted by Section 506.3 for single-story buildings equipped with fire sprinklers. The allowable area could also be increased for frontage in accordance with Section 506.2, depending upon the amount of frontage that the Group A portion has, relative to its own perimeter. The important point is that the area limits for each Group A-1 or A-2 occupancy are based upon Section 503.1, not the tabular values of Table 503. Thus, because Section 503.1 states that the allowable area is limited to the values in Table 503.1 except as modified hereafter, the allowable increases given in Section 506 would be applicable. Also note that each Group A-1 or A-2 occupancy is evaluated on its own and not as an aggregate (i.e., the area of the Group A-1 and A-2 occupancies would not have to be added together).

Item 3 states that all exits from the Group A-1 or A-2 occupancy must discharge directly to the exterior. While other paths of travel available to the occupants are permitted to discharge back into the building, the required exits must discharge directly to the exterior such that an occupant in the Group A-1 or A-2 portion can exit the space without having to pass through other parts of the building. This eliminates the hazard of having to pass through higher fuel load areas.


----------



## el cholo (Jul 20, 2014)

cda said:
			
		

> Will let someone else address the seperation question.But the building official is going to set the occupant load, so if you have enough exit width , even if you call the whole thing an A what does it matter??
> 
> """I am tempted to just call out the entire space as an A-2 & be done with it? But that means the max. occupant load sign the Fire Marshall will put up on the building will not be correct per Table 1004.1.1.""
> 
> ...


So servery is just the counter space or buffet between the Dining room and Kitchen.  Where someone will grab their meals along with drinks & whatnot, paying (Mercantile) & then going to the dining area.  It doesn't have seating area, so I don't think it should be Assembly & it's not part of the kitchen.  This A-2 restaurant is more cafeteria like, not a sit-down restaurant with waiters.

So from that 2009 commentary, the Section 507.3.1 seems to contradict everything about non-separated occupancies, regarding Assembly spaces.

Also, this sentence is confusing, "*Group A-1 or A-2 buildings would not be permitted as standalone unlimited area buildings."*  But Table 503 even shows that A-1 through A-5 can be UL if construction type is min, Type IB.  What is going on out here!


----------



## cda (Jul 20, 2014)

"""So servery is just the counter space or buffet between the Dining room and Kitchen. Where someone will grab their meals along with drinks & whatnot, paying (Mercantile) & then going to the dining area."""""

I would either include it with the dining or kitchen and not make it another occupancy type


----------



## cda (Jul 20, 2014)

http://www.specsandcodes.com/Articles/The%20Code%20Corner%20No.%2017%20-%20Allowable%20Building%20Area%20Part%202.pdf

http://www.specsandcodes.com/Articles/The%20Code%20Corner%20No.%2014%20-%20Building%20Classification%20Part%201%20-%20Occupancies.pdf


----------



## el cholo (Jul 20, 2014)

cda said:
			
		

> """So servery is just the counter space or buffet between the Dining room and Kitchen. Where someone will grab their meals along with drinks & whatnot, paying (Mercantile) & then going to the dining area."""""I would either include it with the dining or kitchen and not make it another occupancy type


Yeah, I think I'm just going to stick with A-2 occupancy for the whole thing & count this as Assembly (unconcentrated).  Thanks!


----------



## cda (Jul 20, 2014)

I would break out the kitchen

I just see to many people sub divide a business when I don't think it is necessary or matters


----------



## kilitact (Jul 20, 2014)

Is the day care classified has an E or I-4 occupancy?


----------



## el cholo (Jul 21, 2014)

kilitact said:
			
		

> Is the day care classified has an E or I-4 occupancy?


Not sure what they are, I know it's been there since at least 2001 if that means anything.


----------



## steveray (Jul 22, 2014)

Wouldn't that need a "horizontal firewall" to separate the spaces under the garage above? Which doesn't exist in my code, but I heard it is coming in the newer ones...


----------



## JBI (Jul 22, 2014)

el cholo, IMHO the 'servery' need not be seperately identified as 'mercantile' simply because that is where the money exchanges hands any more than the cashiers' station in a regular restaurant. For occupant load you could use 'standing space' for the severy and increase the occupant load even more, or simply use the unconcentrated factor and keep the OL down a bit. Also, no need to 'classify' the toilet rooms/corridors. That'd just be silly, wouldn't it?

steveray, Walls are vertical so there never will be a 'horizontal firewall' ('firefloor' maybe...). There are however ways to create seperations horizontally within a building. The EBC uses horizontal seperations as does the BC. They are not called 'firewalls' and do not create 'seperate buildings' the way a firewall does. But their use in the EBC allows flexibility for existing buildings. It is only a matter of time before the codes allow them to be used in a similar fashion for new construction as well.


----------



## kilitact (Jul 22, 2014)

With the parking garage, Section 509, would allow a horizontal firewall. Are you changing the original approved, permitted design of the building?


----------

