What is a Business Occupancy?

MeyerFire University | LS101.10

By Chris Campbell, PE

SUMMARY

• One-Page Summary [PDF]

CODE & STANDARD REFERENCES

• IBC – 2021: Section 304.1 Definition of Business Occupancy (with examples)
• IBC – 2021: Section 303.1.2 Small Assembly spaces that quality as Business Occupancies
• IBC – 2021: Section 311.1.1 Small storage areas as accessory to Business Occupancies

---

TRANSCRIPT

What is a Business Occupancy? 

INTRODUCTION 

A Business occupancy, also known as a Group B occupancy, is an occupancy involving “the use of a building or structure, or a portion thereof, for office, professional or service-type transactions, including storage of records and accounts” as written in IBC Section 304.1. 

More simply stated, a business occupancy involves a space used for business purposes. 

Unlike other occupancy types, the IBC does not divide Business occupancies into sub-types, so all Business occupancies are under the “Group B” designation. The IBC does provide a list of examples of Group B occupancies but note that this is not an exhaustive list. There can certainly be other types of business activities that would still be considered a Group B occupancy.

EXAMPLES OF GROUP B OCCUPANCIES

The example list includes: Airport traffic control towers, Ambulatory care facilities, Animal hospitals, Banks, Barber or beauty shops, Car washes, Civic administration facilities, outpatient clinics, Dry cleaning and laundries, pick-up and delivery stations, Educational occupancies for students above the 12th grade, Electronic data processing facilities, Small Food processing establishments, testing and research laboratories, Motor vehicle showrooms, Post offices, Print shops, Professional service facilities, Radio and television stations, Telephone exchanges, and Training and skill development facilities that are not in a school or academic program. 

In addition to this list, there are a few additional situations where business occupancy may be present.

SMALL ASSEMBLY USE SPACES

As described in the Assembly occupancy video, small assembly spaces with an occupant load of less than 50 or with an area less than 750 SF are considered Group B occupancies. This is true even if the room or spaces are used for assembly purposes. Note that the occupant load factor for such rooms is based on IBC Table 1004.5, which is based on the function of the space and not the occupancy classification. 

So a 500 SF conference room located within a Business occupancy would not be considered an assembly occupancy, but rather part of the Business occupancy.

But you would still apply the occupant load factor of 1 person per 15 net square feet from IBC Table 1004.5 for Assembly: Tables and Chairs functions. 

Another common misconception is classroom spaces for students above the 12th grade.  

EDUCATIONAL CLASSROOMS

Even if such a room has the name education in the title, it is not a Group E occupancy. Rather, it would be a Group B occupancy for a typical classroom and a Group A-3 occupancy for a larger lecture hall. 

And finally, many designers make the mistake of classifying small storage rooms within a business occupancy as a separate Group S storage occupancy.  

STORAGE AREAS

The code has a specific provision for this situation in Section 311.1.1, which states that “A room or space used for storage purposes that is accessory to another occupancy shall be classified as part of that occupancy.” So those small storage rooms within a business space can just be considered part of the business occupancy and should not be considered a Group S occupancy. 

SUMMARY

So, what is a business occupancy?  

In short, it is a building, structure or space used for office, professional or service-type transactions. The IBC provides a lengthy list of examples of business occupancy, and remember that all business occupancies are within the same Group B designation. Remember that small spaces used for assembly purposes are often classified as business occupancies as well. 

I am Chris Campbell, this is MeyerFire University.