Do I need to use fire rated drywall on the inside of this chase?

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Squints2See

New Member
Apr 14, 2022
2
WV
Hi folks,
I recently tore out a wood burning manufactured fireplace in a multi-story condo building. It was a corner unit and my plan is to just close up the wall behind where it was so the room is rectangular again. Once I ripped out the drywall that was behind the unit I opened up access to a huge chase where the flue pipe for my unit plus an additional flue pipe for a unit on a floor below me is. I am wanting to be sure that I seal it up correctly and safe. I have not been able to find any codes on the ICC website in the IBC or the mechanical building code book stating that I need to use type x drywall, double layers, etc... The flue pipe had a tag right on it stating to keep combustible materials at least 1" away. The chase wall had several layers of drywall (one of them 1" thick which I have never seen) originally. I don't know why.

I've attached some pics.

IMG_20220409_145948934.jpg


Does anyone know for sure or have any ideas if I need to do a layer of fire rated drywall on the chase side, with fire rated drywall on the room side as well? Or can I just insulate and use standard drywall on the inside and call it a day?

Any help would be appreciated. Also, the location is in WV and in a very rural area where there are no local inspections done and to my knowledge no amendments/county specific codes. They just follow the IBC/IRC, etc...

Thanks,
Todd IMG_20220409_133010918.jpg
 

snobuilder

Feeling the Heat
Dec 16, 2021
432
WI
That 1" drywall is type X Shaftliner and is rated for 120 minutes. It is important that it gets replaced as found.
 

Squints2See

New Member
Apr 14, 2022
2
WV
That 1" drywall is type X Shaftliner and is rated for 120 minutes. It is important that it gets replaced as found.
Snobuilder, thanks for the response. I assume I would be fine to use two layers of 5/8" type X then in its place? I'm not going to be able to get shaftliner up four flights of stairs very easily nor can I get it in time as I am going up there this weekend to continue work on it. Is this required by code to your knowledge? Thanks
 

begreen

Mooderator
Staff member
Nov 18, 2005
93,729
South Puget Sound, WA
Go to the local building department and ask the inspecting authority what is required. If there is no fireplace or flue there the code may be more lenient.
 

snobuilder

Feeling the Heat
Dec 16, 2021
432
WI
Unfortunately for you, you opened up a common wall that served more than your unit which increases the liability beyond your dwelling.

Assuming you will be closing it up on your own, then yes , steel studs and 2 layers of 5/8" firecode drywall at a minimum to protect your unit as well as any others abutting that chase.
 
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