occupant load calculations for multiple occupancies

[VAC]

Sum and then round up is how I have always done it for the entire floor. Basically when you are doing a room by room calculation it is a net calculation versus a gross calculation. If the entire floor is a "B" occupancy and you calculate the entire floor at 100 sq ft per person you will probably not exceed the sum of all occupiable spaces when adding up all the fractional amounts' and then rounding up to the next whole number.

[BE] FLOOR AREA, GROSS. The floor area within the inside perimeter of the exterior walls of the building under consideration, exclusive of vent shafts and courts, without deduction for corridors, stairways, ramps, closets, the thickness of interior walls, columns or other features. The floor area of a building, or portion thereof, not provided with surrounding exterior walls shall be the usable area under the horizontal projection of the roof or floor above. The gross floor area shall not include shafts with no openings or interior courts.

[BE] FLOOR AREA, NET. The actual occupied area not including unoccupied accessory areas such as corridors, stairways, ramps, toilet rooms, mechanical rooms and closets.

Thank you! agree! and this is how I've done it, (entire floor as B) but I was stumped about the request.
It was in particular regarding a "B" occupancy with a Conf. Room, (accessory only 200 sf) and a couple of other areas like that (a small exercise room and a lounge room) so first it was that each room's use is different, so I couldn't classify them as B. I had to calculate load (based on use) individually (fine, I get that even though I didn't think it was necessary but what do I know?!....)

Then, came the rounding up for each, which was news to me based on how I had have done it...(currently using IBC 2018) If I calculate the load based on use for each room, I end up with fractions (like Conf. Rm would be 13.33) so rounding up each and then rounding up again puts me over 49...

Maybe I need a chat with the AHJ

 

[VAC]

Each space has to have adequate exits for its occupants, so you should round up for each room. I would do a separate calculation with the total areas for each occupancy for building exits and plumbing. That way you wouldn't have a lot of "phantom" occupants fro rounding many 1.5 person offices up to 2 each.

I get that and pretty much how I've done it for years. The issue is I have been asked to classify the use of each room differently (Conf. Rm and small employee lounge, etc as "A") even though the space is "B". Which now creates a few "phantom" occupants... hence my dilemma. Thanks for your input. At least I know I haven't been doing something unique

 

[Sifu]

Who asked you to classify them as A? Small conference rooms would not be classified as A, they would be B or the same as the main occupancy. But, as you say, load is based on use, not classification so in your application it wouldn't matter. But, if you classify them as A, then you have to account for that in your mixed-use strategy.

 

[ADAguy]

Is there a maximum distance allowed from an egress door to corridor for a room with 49 occupants?

 

[mtlogcabin]

Depends on Occupancy Type and if sprinkled or not. Anywhere from 25 feet to 125 feet