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Chicago code drywall basement ceiling

Kyle Miller

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Joined
Feb 13, 2019
Messages
7
Location
Chicago
Hello all! I'm finishing the basement of a triplex condo in Chicago (townhouse style with a shared entry/common space with one unit). The developer didn't consider a future finished basement when it was it was converted to condos 20 years ago so there are conduit and pipes running under the joists. Due to the low ceiling and the fact there would be soffits littered on the ceiling, I plan on spraying the ceiling black (it actually looks surprisingly good). Before I do it, I want to make sure Chicago allows open joists in a living space. There is fire resistant drywall on the ceiling near the water heater and furnace that will remain. Also, the new bathroom will have a finished ceiling. Joists have 16" spacing. The work is permitted so there will be a final inspection.
 
First off, welcome.

What type of joists are they? I-joists, nominal lumber, etc? Dimensional size?

And what code and cycle was this permitted under?
 
Seems they would have said something during plan review, unless the entire basement was not shown,

Do you have required exit/ emergency exit?
 
The following code section is from the 2015 IRC, and speaks to requirements for GWB on underside of floors. This is not for horizontal separation between units however, if you have stacked units, that will be a different answer.

upload_2019-2-13_9-31-8.png
 
Wow! Thanks so much for the fast replies. This is my first project as a general contractor so I apologize for my ignorance. I'm trying to learn as much as I can. I have attached pictures of the ceiling. This is the only unit between the slab and the roof. There are condo units sharing walls on two sides.

I talked to the architect and said he doesn't believe the ceiling can be open since it's a multi-unit but would be allowed in a SFH. He wasn't confident and said he would look into it. I have an electrical rough inspection tomorrow so I plan on asking the inspector to shed some light.

First off, welcome.

What type of joists are they? I-joists, nominal lumber, etc? Dimensional size?

And what code and cycle was this permitted under?

The joists are 2x10 lumber.

The permit states "INTERIOR BUILD-OUT TO EXISTING BASEMENT, OCCUPANCY A-2 TO REMAIN, CONSTRUCTION TYPE 3B TO REMAIN"



Seems they would have said something during plan review, unless the entire basement was not shown,

Do you have required exit/ emergency exit?

It's a walk-out basement, there are two means of egress.
 
Sorry! I can't figure out how to edit a post... https://imgur.com/a/9Goc46D


You have to put a quarter in the coin slot.


Or become a supporting member of the forum. and for that low low price, you get a lot of valuable info.




I am not into residential especially Chicago, they have their own code. But I think you will have to sheetrock it.


What will the space be used for, general living or sleeping?
 
Scratch my original comment - Chicago has its own building code that is not based upon the ICC format. You will need to either wait for the building inspector or hopefully someone familiar with Chicago's codes will chip in here.

Best of luck!
 
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You have to put a quarter in the coin slot.


Or become a supporting member of the forum. and for that low low price, you get a lot of valuable info.




I am not into residential especially Chicago, they have their own code. But I think you will have to sheetrock it.


What will the space be used for, general living or sleeping?

I didn't know there was a membership option. I will definitely consider that. I'll be needing a lot of help. Are there Chicago people on the forum?

I'm adding a bedroom and bathroom to the basement.
 
Is the building actually in the city limits of chicago??


https://www.chicago.gov/city/en/depts/bldgs/provdrs/bldg_code.html

Yes it is in Chicago. I've been looking at the building code but I'm struggling to interpret it or find information for this specific situation. I'm almost 100% positive that SFH's are allowed to have an open ceiling in the basement but I can't find anywhere where it distinguishes the requirement for fire code between an SFH or a condo building (more specifically a condo without another unit above it. I would think that would exist if it's allowed in one but not the other. I talked the electrical inspector that did the rough inspection this morning and he said I don't need added fire protection. My architect just texted me to confirm that I do. I'm considering adding an intumescent coating as a worst case scenario. Even at the high cost, it will probably be cheaper than adding soffits, drywall and changing light fixture placement.
 
in some of the rest of the world there is IRC that covers single family houses

and IBC which covers all the rest

Not sure if Chicago has a separate code for both??

In them there is a chapter on separation when or if not required


Hoping someone on here will give you the base code requirements out of those code books.
 
Yes it is in Chicago. I've been looking at the building code but I'm struggling to interpret it or find information for this specific situation. I'm almost 100% positive that SFH's are allowed to have an open ceiling in the basement but I can't find anywhere where it distinguishes the requirement for fire code between an SFH or a condo building (more specifically a condo without another unit above it. I would think that would exist if it's allowed in one but not the other. I talked the electrical inspector that did the rough inspection this morning and he said I don't need added fire protection. My architect just texted me to confirm that I do. I'm considering adding an intumescent coating as a worst case scenario. Even at the high cost, it will probably be cheaper than adding soffits, drywall and changing light fixture placement.


Paint may not be accepted
 
I have finally received a firm answer (though I'm not sure where it can be found in Chicago's building code). I got in touch with a Chicago building inspector. He said one hour fire rating is required in floor joists for all levels of residential buildings with three or more units. One hour rated fire retardant coating is acceptable but it must be included in the plans. Hopefully this helps anyone who might be looking for this answer in the future. I appreciate all of your help.
 
type III-B construction requires 1 hour fire rated floor/ceiling systems, and any beams or columns supporting this floor/ceiling must also be 1 hour fire rated.
The section you were quoted was Table 13-60-100.
 
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