1. ATTENTION returning members. If you are coming here from the old forum for the first time, you will need to reset you password. However, we had an email problem getting password reset links set out to a lot of the email addresses. That problem is temporarily rectified but IF you still have an issue, email me direct at info@thebuildingcodeforum.com and I will give you a temporary password.
    Dismiss Notice
  2. Welcome to the new and improved Building Code Forum. We appreciate you being here and hope that you are getting the information that you need concerning all codes of the building trades. This is a free forum to the public due to the generosity of the Sawhorses, Corporate Supporters and Supporters who have upgraded their accounts. If you would like to have improved access to the forum please upgrade to Sawhorse by clicking here: Upgrades
    Dismiss Notice

IBC 2018 Concentrated Business Occupancy

Discussion in 'Commercial Building Codes' started by Michael Schirmer, May 16, 2019 at 10:29 AM.

  1. Michael Schirmer

    Michael Schirmer Registered User

    Joined:
    Thursday
    Messages:
    9
    Likes Received:
    0
    Hi. I'm new here and found this via another forum where I was told of this forum. Glad to see a place where building code can be discussed.

    With the introduction of the IBC 2018, Business occupancy has been subdivided in Table 1004.5 and then Section 1004.8. Now the occupancy for Business is 1:150 and then there is "Concentrated Business Use" where the number of seats is counted. Sure, it says for call centers, etc, but that isn't how the cities around my area are using it like Plano, Texas. They are counting the cubicle, no matter the use. I'm curious if anyone else has worked with cities with IBC 2018 and what are your understandings? There are a few mixed answers in our office on how to determine the floor space of the "Concentrated Business Use (CBU)" area. Do you count only the floor space under the cubicles, the entire region of cubicle area or the entire open office area where the cubicles exist, which could include areas that could be classified as a hall?

    Any thoughts on this?
     
  2. RLGA

    RLGA Sawhorse

    Joined:
    Oct 18, 2009
    Messages:
    1,568
    Likes Received:
    469
    Section 1004.8 states the actual occupant load, but not less than 50 sq. ft. of "gross occupiable floor space." Thus, I would treat it just like you would for the standard gross floor area for business areas per Table 1004.5.
     
  3. Tim Mailloux

    Tim Mailloux Registered User

    Joined:
    Feb 12, 2018
    Messages:
    133
    Likes Received:
    13
    So the new concentrated load is the high number using either 1 person per 50sf of gross floor space or the actual number of people?
     
  4. RLGA

    RLGA Sawhorse

    Joined:
    Oct 18, 2009
    Messages:
    1,568
    Likes Received:
    469
    Yes, it's the greater of the two. Per the Significant Changes to the International Building Code (2018 Edition): "...the occupant load must be established at a minimum of one occupant for each 50 square feet."
     
  5. Michael Schirmer

    Michael Schirmer Registered User

    Joined:
    Thursday
    Messages:
    9
    Likes Received:
    0
    So in the example below, which area do you include is sq ft of Concentrated Business Area? Green only? Red only? Red and Blue? This is part of our issue of determining what code implies.

    [​IMG]
     
  6. RLGA

    RLGA Sawhorse

    Joined:
    Oct 18, 2009
    Messages:
    1,568
    Likes Received:
    469
    Red plus blue and then some (some areas not highlighted would be included in the gross floor area); but I agree with you...this is not a concentrated business use. I bet if you took that gross floor area and divided it by 150 you would get a number very close to the number of cubicles shown.
     
  7. Michael Schirmer

    Michael Schirmer Registered User

    Joined:
    Thursday
    Messages:
    9
    Likes Received:
    0
    The code says
    Thanks. We're going to get that book then. Might be more there that we need clarification.
     
  8. Michael Schirmer

    Michael Schirmer Registered User

    Joined:
    Thursday
    Messages:
    9
    Likes Received:
    0
    I didn't mean to add that first part and dont know how to edit yet.
     
  9. RLGA

    RLGA Sawhorse

    Joined:
    Oct 18, 2009
    Messages:
    1,568
    Likes Received:
    469
    This is a call center floor plan--there's a big difference between what you show and what is shown below.
    [​IMG]
     
  10. Michael Schirmer

    Michael Schirmer Registered User

    Joined:
    Thursday
    Messages:
    9
    Likes Received:
    0
    I agree. The city put out its rule that all workstations fall under the category of "concentrated business". They also give leniency to the lesser number.
     
  11. Michael Schirmer

    Michael Schirmer Registered User

    Joined:
    Thursday
    Messages:
    9
    Likes Received:
    0
    With this plan you show, would you still include the empty open office above office 1 & 2, as well as the corridor area for the "concentrated business"? Just reclarifying.
     
  12. RLGA

    RLGA Sawhorse

    Joined:
    Oct 18, 2009
    Messages:
    1,568
    Likes Received:
    469
    No, I would apply the 1:150 OL factor to that space (unless it has another defined use not indicated), as well as the open area just outside of those offices.
     
  13. Michael Schirmer

    Michael Schirmer Registered User

    Joined:
    Thursday
    Messages:
    9
    Likes Received:
    0
    That is what I was assuming. I think the first city I had to use the 2018 code for confused me on how to interpret. Texas allows cities to choose the code. There is actually one city we deal with still on 2006 codes.
     
  14. Tim Mailloux

    Tim Mailloux Registered User

    Joined:
    Feb 12, 2018
    Messages:
    133
    Likes Received:
    13
    Remember that the gross floor area for the business use included in the calculation is everything with a roof over it, Corridors, toilets, stairs shafts, elevator shafts, mechanical shafts, etc. minus any floor area net functions of space such as conference rooms.
     
    Michael Schirmer likes this.

Share This Page