Allowable Area for Non-Sprinklered Existing Building

[ETThompson]

We're working on renovating an existing structure (now a maintenance building, it will be converted to offices/fitness/storage). We're under the Ohio Building Code 2017 which is based on the 2015 IBC. Construction Type is IIB, and this is all on one story at grade.

The majority of the 15,500sf building is classified as B (offices, fitness). The storage area (a mailroom for a college) is S-1. Per 508.4 there is no separation requirement between these two, even if non-sprinklered (which is the intent).

Do we still though have to approach the allowable area as "worst case" (S-1, which has a tabular area of 17,500, as opposed to B which is 23,000). I'm assuming we do (and we pass either way, so it's mostly out of interest that I ask).

Thanks

 

[RLGA]

If using the separate occupancies method, treat each occupancy separately in regard to ratios (actual/allowable), whether they are required to have a fire-rated separation or not.

 

[steveray]

I would think the worst case would be fitness A3?

 

[RLGA]

I would think the worst case would be fitness A3?

Only if the occupant load of the fitness area exceeds 49 (based on 50 sq. ft. per occupant using the "Exercise rooms" load factor per Table 1004.5). I have used the Group B occupancy for fitness areas because they are usually of limited size when provided as an amenity to the primary function.

 

[steveray]

I'd have to think a bit more on that in the, Ch. 10 does not always equal Ch. 5 sense..... accessory would be limited to 10%...At 50 per sqft that could be almost a 2500 ft room....But yes, accessory use is a way to go...

 

[steveray]

And....Look at Ch 10 for COO in the IEBC...1012 in particular might have some relief based on which way you are going on hazards...S and B are usually close...

 

[RLGA]

An assembly occupancy is described in Chapter 3 as for "civic, social or religious functions; recreation, food, or drink consumption or awaiting transportation." Section 303.1.1 considers small assembly spaces to be those where the occupant load is less than 50--there is no mention of floor area.

You use Table 1004.5 to determine the occupant load based on the "Function of Space." Since they specifically have a load factor for "Exercise rooms," that should be the factor used (this load factor considers the floor area occupied by exercise equipment). If the space is for yoga or other similar types of exercise, using the Unconcentrated Assembly load factor (or the Classroom load factor, if part of class instruction) would be more appropriate.

 

[steveray]

1. A room or space used for assembly purposes with
an occupant load of less than 50 persons and
accessory to another occupancy shall be classified
as a Group B occupancy or as part of that
occupancy.

It's a little dicey....I'm probably with you Ron, but I would really need to see it.....

 

[RLGA]

1. A room or space used for assembly purposes with
an occupant load of less than 50 persons and
accessory to another occupancy shall be classified
as a Group B occupancy or as part of that
occupancy.

It's a little dicey....I'm probably with you Ron, but I would really need to see it.....

There is no definition of accessory in the IBC. Even the "accessory occupancies" method in Section 508.2 does not define it beyond stating that they are "ancillary to the main occupancy." However, the use of "accessory" in Section 303 does not necessarily correlate with or is connected to Section 508.2.

Here is the first dictionary definition (using the adjective form):

Accessory: "contributing to or aiding an activity or process in a minor way; subsidiary or supplementary."​

​

Now, I assume the building is a campus office building (the OP mentioned a college mailroom). An exercise room would contribute to or aid in a minor way to the health and welfare of employees.

Even if the space was leased out for business purposes, the space could still be considered accessory. You referenced the first subparagraph in Section 303.1.2, which addresses small assembly spaces in buildings of any size. However, Section 303.1.1 (the section I referenced) refers to small buildings and tenant spaces (consider multiple businesses in a college student union, which is what I first assumed this building was). An exercise area for students leased and operated by a tenant could also be considered accessory in the larger context of the building use, which might be a combination of business, mercantile, and assembly occupancies.

This is the approach I have used over the past two and a half decades in code compliance and I never had any push-back from a code official or plans examiner on this interpretation.

 

[steveray]

Ron, I respect you and think you are a really smart guy and in this case are likely to be correct.....Like I said, I would need to see it.....

If I blanketly accepted the "I've been doing it for 25-30 years" argument, I would approve a lot more stuff....I get paid to be skeptical...

 

[RLGA]

Ron, I respect you and think you are a really smart guy and in this case are likely to be correct.....Like I said, I would need to see it.....

If I blanketly accepted the "I've been doing it for 25-30 years" argument, I would approve a lot more stuff....I get paid to be skeptical...

The Commentary does not explain each occupant load factor listed (which would probably add another twenty pages to the book). All we have left is our personal interpretations, and we hope they align with those reviewing our documents.

Just consider this regarding exercise rooms:

• Exercise equipment takes up a lot of space. Look at the occupant loads for educational shops, vocational rooms, and locker rooms; all have a lot of equipment or lockers that take up floor space that people cannot occupy.
• Even exercise rooms with no equipment could require 50 sq. ft. per person, depending on the type of exercise activity. The average human dimensions are 6 feet from fingertip to fingertip and 7 feet from the feet to fingertips (with arms above head). Then add 6 inches to ensure you do not hit anyone adjacent to you. If you are on your back or stomach, you would need almost 49 square feet (48.75 inches to be exact) to move your arms and legs in full motion. I would say that is pretty close to 50 sq. ft.

I have heard the arguments, "well, they could move out the equipment," or "they could use the space for other purposes," or my favorite, "well, John McCain could decide to give a speech, and hundreds of people would show up" (regarding a large publicly accessible court for a museum where we were trying to justify a low occupant load amongst the outdoor art pieces).

You can "what if" anything to oblivion, but you only are given the intent for the building or space in the here and now. No owner can be forced to make their big box store comply with assembly requirements because it could be converted into a theater months, years, or decades from now.

It is acceptable to be skeptical when the situation warrants it, but constantly being so hampers progress.

 

[steveray]

The Commentary does not explain each occupant load factor listed (which would probably add another twenty pages to the book). All we have left is our personal interpretations, and we hope they align with those reviewing our documents.

Just consider this regarding exercise rooms:

• Exercise equipment takes up a lot of space. Look at the occupant loads for educational shops, vocational rooms, and locker rooms; all have a lot of equipment or lockers that take up floor space that people cannot occupy.
• Even exercise rooms with no equipment could require 50 sq. ft. per person, depending on the type of exercise activity. The average human dimensions are 6 feet from fingertip to fingertip and 7 feet from the feet to fingertips (with arms above head). Then add 6 inches to ensure you do not hit anyone adjacent to you. If you are on your back or stomach, you would need almost 49 square feet (48.75 inches to be exact) to move your arms and legs in full motion. I would say that is pretty close to 50 sq. ft.

I have heard the arguments, "well, they could move out the equipment," or "they could use the space for other purposes," or my favorite, "well, John McCain could decide to give a speech, and hundreds of people would show up" (regarding a large publicly accessible court for a museum where we were trying to justify a low occupant load amongst the outdoor art pieces).

You can "what if" anything to oblivion, but you only are given the intent for the building or space in the here and now. No owner can be forced to make their big box store comply with assembly requirements because it could be converted into a theater months, years, or decades from now.

It is acceptable to be skeptical when the situation warrants it, but constantly being so hampers progress.

Yep....Weights, yoga, crossfit, jazzercise, it would all matter....Have to see it and get FM buy in....As they get to enforce it in perpetuity....