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Can a B accessory exiting through A-2 space have 100' of CPET?

Y

Yikes

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Joined
Nov 2, 2009
Messages
4,105
Location
Southern California
Proposed A-2 restaurant 24'x65', two stories plus basement, sprinklered, built out to property lines on both sides and rear (it's a very narrow lot!). Front court (open to the sky) will have an outdoor bar, dining patio, and 12" tall wheelchair ramp to public R.O.W.

  • 2nd floor is <750 SF, and has 45 occupants going down a stair and discharging directly to the exterior front dining patio / exit court.
  • Ground floor has some indoor dining, elevator, and the main kitchen.
  • Basement has a bar/dining area, <750 SF, and has only on egress path, a single stair going up to the first floor. Including the stairway path, CPET from basement though first floor to exterior front dining patio / exit court is greater than 75' but less than 100'.
303.1.2 allows the basement at <750 SF to be classified as a "B" occupancy as an accessory to the A2 occupancy. This buys us 100' of CPET per table 1006.3.3(2) footnote b.
Once the basement occupants join up with the first floor occupants, the cumulative occupancy load at the first floor exceeds 49 and now the first floor is definitely A-2 occupancy.

Q1: Does having the B accessory exit through the A-2 somehow limit the B occupancy to 75' CPET instead of the 100' normally allowed to a sprinklered B occupancy? does the B Occupancy get treated like an "A" occupancy for CPET just because it passes through the CPET?

Q2: When a B occupancy is accessory to an A occupancy per 303.1.2 (either exception #1 or 2), does it still need to have the 1 hr. occupancy separation described in table 508.4?
 
So are the basement and 2nd floor only partial? Main floor is 24x65 correct?
Can you call it mixed use non-separated instead of trying to claim the accessory use for the basement (<10% of main occupancy combined)?
If non-separated however, I would think that you would be limited to the more stringent 75'.
 
mwskopf said:
So are the basement and 2nd floor only partial? Main floor is 24x65 correct?
Can you call it mixed use non-separated instead of trying to claim the accessory use for the basement (<10% of main occupancy combined)?
If non-separated however, I would think that you would be limited to the more stringent 75'.
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Thanks for helping with this.
1. Yes, only partial. The basement also has a small room with restaurant supply storage.
2. Yes, main floor is 24x65.
3. Calling it non-separated would IMO limit the CPET to 75'. Separating it is easy, we can add a door at the stair landing.
 
Ok,
In that case, I would look at separating the smaller basement assembly(B), and then have a discussion w/ the AHJ about using the B occ CPET for that group. My gut says that they will make you use the A-2 since it is the "main" occupancy however.
On the exiting, aren't you going to need two exits due to the occ load being greater than 49? Also, check me on this, but won't the CPET end at the side walk as opposed to the front doors? I may be digressing
My $.02
 
The restaurant is in a mild climate. The entire front wall opens up (22' wide between the side walls). The occupants from the basement and upstairs reach grade level at 10' away from this opening, so the 22' wide opening will achieve exit separation once those groups combine to 50+ occupants.

I appreciate the digression. It is interesting to note that the remoteness requirement (1/2 diagonal measurement, or 1/3 diagonal for sprinklered buildings) in 1007.1.1 applies to two or more "exits or exit access doorways".
Once we are outdoors in the front dining patio / exit court, which is open to the sky, I believe the exit has terminated and we are in the "exit discharge" portion of the MOE system (IBC/CBC 1028). I don't believe the remoteness requirement in 1007.1.1 applies to the exit discharge. If it did, most flag lots could never be developed.
 
Well, back to the original question... I would again have a chat w/ your AHJ about your plan. I had to do something similar just this morning.
Cheers
 
Yikes said:
The restaurant is in a mild climate. The entire front wall opens up (22' wide between the side walls). The occupants from the basement and upstairs reach grade level at 10' away from this opening, so the 22' wide opening will achieve exit separation once those groups combine to 50+ occupants.

what happens on a rainy cool day when the owner keeps that operable wall closed?
Click to expand...
 
steveray said:
I'd call BS on the basement being B accessory.....It's a restaurant on all floors....
Click to expand...
looking at the code commentary to 303.1.2 I agree this is BS......"a classification of other than Group A is permitted. In both cases, the purpose of the assembly space must be accessory to the principal occupancy of the structure (i.e., the activities in the assembly space are subordinate and secondary to the primary occupancy)".
 
Tim, this restaurant is located in a Southern California beach community with a very mild climate. Daytime highs even in the coldest winter months are in typically the 60s, and in the dead of night when the restaurant is closed, it doesn't get much below 50.
It is a "fair weather" business, as are the nearby street cart / food truck vendors. It is not uncommon in this community to have some cafe-type restaurants with a 100% open wall configuration facing the street. If it gets cold, they turn on the infrared space heaters.
In event of rain, they either keep the moveable wall open, or they can choose to shut down the restaurant altogether.
 
Are you saying that the only way that the exit separation is compliant is with the entire operable window system in the open position? There is no compliant man door as a part of the operable window system that allows compliance when these operable windows are closed? That would be a no way jose for me if that is the case.
 
JPohling said:
Are you saying that the only way that the exit separation is compliant is with the entire operable window system in the open position? There is no compliant man door as a part of the operable window system that allows compliance when these operable windows are closed? That would be a no way jose for me if that is the case.
Click to expand...
Hmmm... you might be right on that one...
I was thinking of it as similar to a security grille, but I see that in CBC 1010.1.4.5 those are limited to B, F, M and S occupancies only needing a single exit, not at an A-3 occupancy.
 
I'm not seeing any way to call the basement anything other than another room of the A-2 restaurant occupancy. In fact, I just reviewed plans for a 2-story restaurant where the designer (an unlicensed person playing architect, but that's a separate issue) tried to claim that the dining area on each floor was less than 750 square feet, so the occupant load was under 50 and therefore he wanted to classify each story as Use Group B. Of course, his 745 s.f. ignored the kitchen space, corridor space, storage space, and standing room at the hostess station, so we didn't accept the concept of less than 50 on each floor. Beyond that, it's an existing building with an open stair connecting the two stories, so we (and the fire marshal) consider it to be one occupancy, with an occupant load for the overall restaurant of about 135 people. The code provision for classifying a restaurant as a Business says

303.1.1 Small buildings and tenant spaces. A building or
tenant space used for assembly purposes with an occupant
load of less than 50 persons shall be classified as a Group B
occupancy.

That says "building" or "tenant space." If one tenant occupies the entire building, then you have to use the total occupant load in determining if this section applies.

To get into the other exceptions listed in IBC 303.1.2, the space under consideration has to be accessory to some other use group -- such as a conference room in a business, or a classroom in a manufacturing plant. I wouldn't apply that to allow an A-2 occupancy to be accessory to an A-2 occupancy and thereby escape being an A-2 occupancy. That makes no sense at all.
 
Yankee Chronicler said:
I'm not seeing any way to call the basement anything other than another room of the A-2 restaurant occupancy. In fact, I just reviewed plans for a 2-story restaurant where the designer (an unlicensed person playing architect, but that's a separate issue) tried to claim that the dining area on each floor was less than 750 square feet, so the occupant load was under 50 and therefore he wanted to classify each story as Use Group B. Of course, his 745 s.f. ignored the kitchen space, corridor space, storage space, and standing room at the hostess station, so we didn't accept the concept of less than 50 on each floor. Beyond that, it's an existing building with an open stair connecting the two stories, so we (and the fire marshal) consider it to be one occupancy, with an occupant load for the overall restaurant of about 135 people. The code provision for classifying a restaurant as a Business says

303.1.1 Small buildings and tenant spaces. A building or
tenant space used for assembly purposes with an occupant
load of less than 50 persons shall be classified as a Group B
occupancy.

That says "building" or "tenant space." If one tenant occupies the entire building, then you have to use the total occupant load in determining if this section applies.

To get into the other exceptions listed in IBC 303.1.2, the space under consideration has to be accessory to some other use group -- such as a conference room in a business, or a classroom in a manufacturing plant. I wouldn't apply that to allow an A-2 occupancy to be accessory to an A-2 occupancy and thereby escape being an A-2 occupancy. That makes no sense at all.
Click to expand...
Welcome to the forum and thanks for bringing your A game!....Go New England!
 
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