Egress and Fire Escape Ladders 1

[NMCivil]

We're being told by our site FPEs that we need to add a stairwell (inside or out) to an existing building to meet emergency egress requirements. This building, designed and built in the 80s, has 3 floors that are solely served by elevators and ladders. There are five levels total, the second level is served by a stairwell in addition to the elevator. Above the second floor, square footage is reduced and there is no room for the stairwell to continue up. Space on each floor is relatively limited (~2100 sf with floor openings in each floor), but maintenance requirements result in occupancy greater than 3 persons. This is not a storage facility.

Am I wrong thinking that the addition of the stairwell to this building is excessive? I assume that the building was built in accordance with the codes active at the time of its design and construction. In accordance with NFPA 101, Section 7.2.9.2.1 states that "approved existing ladders complying with the edition of this code that was in effect when the ladders were installed shall be permitted." Help me understand this please, do we need to pursue the stairwell addition, or should we be okay based on code of record?

Thanks for the help and insight.

 

[cdafd]

So is there some remodeling going on??

Trying to figure out what triggered the requirement ??

 

[NMCivil]

Good question, no remodeling going on at all. In fact, no construction in the vicinity of the building.

The FPE (one of ~15) brought it up stating, "We must be compliant with the current code."

That was a red flag to me since no one could afford to keep updating their building every time a new code is issued.

 

[stookeyfpe]

Something is missing from this story. Unless the structure was classified as a Special Industrial Building, I don't know how one built a 5 story building without at least one code compliant stair.

 

[cdafd]

What are the top three floors use for??

Which state is this in?

 

[NMCivil]

It is a hoist tower at a mine. The upper three floors are used only for maintenance and accessing the hoist mechanism. These floors extend above the second floor where the rest of the building stops.

 

[cdafd]

Oh.

 

[stookeyfpe]

You don't have a building. You have an equipment platform. The structure is not intended for human occupancy. If my memory is working correctly today, I think you can find a legitimate and reasonable answer in the 2016 IBC, as the term equipment platform is now defined.

 

[NMCivil]

That's a great point. Regardless of whether or not it is enclosed by metal siding, we're still looking at a structure whose sole purpose is to support equipment. I'll start digging through IBC and build my case.
Thanks!

 

[DBronson]

NMCivil:

I don't think your building meets the definition of an equipment platform since these are intended to be part of a building and have a maximum allowable area that's probably way smaller than your structure. My sense of it this should be classified in the Utility and Miscellaneous category (Group U). That category specifically lists Towers as included in the group. My suggestion to you is to contact the local Building Official and discuss the specific life safety issues your team has identified. I very much doubt that two means of egress would be required since the tower is not "occupied" as that term is defined in the code.

Regards,

DB

 

[NMCivil]

DBronson,

I see your point regarding "Group U," but I can't seem to find the maximum allowable area of an equipment platform. Will you please point me in the right direction? Also, it is part of a building, but also extends above that building.

Thanks for the help and input.

 

[cdafd]

EQUIPMENT PLATFORM. An unoccupied, elevated platform used exclusively for mechanical systems or industrial process equipment, including the associated elevated walkways, stairways, alternating tread devices and ladders necessary to access the platform (see Section 505.3).

http://codes.iccsafe.org/app/book/content/2015-I-Codes/2015 IBC HTML/Chapter 2.html

505.3 Equipment platforms.
Equipment platforms in buildings shall not be considered as a portion of the floor below. Such equipment platforms shall not contribute to either the building area or the number of stories as regulated by Section 503.1. The area of the equipment platform shall not be included in determining the fire area in accordance with Section 903. Equipment platforms shall not be a part of any mezzanine and such platforms and the walkways, stairways, alternating tread devices and ladders providing access to an equipment platform shall not serve as a part of the means of egress from the building.

http://codes.iccsafe.org/app/book/content/2015-I-Codes/2015 IBC HTML/Chapter 5.html

 

[cdafd]

Still the question is did the building and egress system meet code when the building was built??

Can you make a building safer, Yes

 

[NMCivil]

cdafd,

Correct that's the crux of the matter, of course we can make it safer, at great expense, but if it was compliant when it was built a solid case would be required. We could also build guardrails around all the sidewalks with fall protection overhead to prevent slips, trips, and falls, but some risk is accepted in our daily lives. I am completely on board with safety, but have to keep the company's best interests in mind and spending $100k on stairwells for a building isn't something to take lightly.

I also appreciate the code references. I found those earlier, but still haven't found any of the "maximum allowable area requirements" that DBronson mentioned.

 

[stookeyfpe]

See IBC Table 503 (2012 edition). This is why I mentioned Special Industrial Occupancies earlier in the post. Look at Section 503.1.1. I beleive this is your occupancy. If you use the occupant load for a mechanical room (300 sq. ft. gross) I highly doubt that you will need two means of egress.

Maybe you should have hired me as your fire protection engineer.

 

[DBronson]

NMCivil:

In the 2012 IBC the area limitation is in 505.3.1. It says that "the aggregate area of all equipment platforms in a room shall not be greater than two thirds of the area of the room in which they are located." Since the project you've described doesn't sound like it really has any rooms I don't think this section applies to the structure at all. As Stookey has pointed out you may be able to use the special industrial occupancy classification though this only exempts the building from the area and height limitations of Table 503. However, it is up to the building official to decide if you can use this classification.

In any case, the issue you have is about egress - not area. According to Table 1015.1 buildings classified as U can have a single means of egress if they have a maximum occupant load of 49 or less. So if you have 2,100 sf x 5 floors=10,500 sf. Dividing this by 300 sf/person gives you an occupancy of 35: 35<49 so you are probably ok if the single means of egress meets the various other code requirements. Unfortunately, this type of building falls between the cracks in the code. I don't think you'll find any explicit language to guide you. That's why I'm urging you to get the local official involved. Remember it's their opinion that counts, not yours.

Regards,
DB