Can you use fireproofing chaulk around NMB?

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bjp_ne_elec

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Have situation where Romex comes through sheet rock ceiling and in to surface mount fluorescent fixtures. It's actually an existing installation, but I may have to replace a light or two. Would like to put some caulk around each hole where the Romex come through. Guess my concern is if the caulk has any effect on the insulation of the NMB. I have definitely seen it used on MC that penetrates the sheet rock - which is obviously the "firewall" (actually ceiling in this case), but I'm not sure if I've ever seen it put arond NMB.

Thanks

Brett
 
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Pierre - thanks. Mine says "PVC, Metal, Copper Pipe, Cables & Metal Ducts" - it's DAP Blockade. It doesn't list any limitations, but it also doesn't list specifics either. I'll hit the DAP website and see if I can find if it's specifically good for NMB.
 
There are a few manufacturers that make expandable polyurethane foam which is suitable for use as a fireblocking material. (not for use as a fire stop on rated walls) The product will be marked with a flame spread of less than 50. (In accordance with ASTM-E-84)

These products are specifically tested for use with non-metallic cables and conduits.

I agree with Pierre that fire rated caulk should be acceptable per the manufacturer's instructions, however fire rated caulk is probably not needed for this application. Are you just trying seal or draftstop the opening?
 
I'm trying to seal the opening, as I'm concerned about the hole where the NMB is penetrating may violate the fire rating of the sheetrocked ceiling. I'm not sure what you mean by "draftstop", and whether that is a term related to spread of fire, or just a term related to heat escaping in to the attic.

Brett
 
While this may not apply to installation, don't forget the derating requirement of 334.80. As far as draft stopping goes, at the top plate, it's more for energy conservation.
 
stickboy1375 said:
I hope you can use fire caulk with NMB, Since i'm required to firecaulk all my holes in the top and bottom plate...:smile:
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If you mean fire caulk the plates in a residential buildings, you most likely do not need to fire caulk most of those holes. Most residential buildings only require fire caulking where the garage is next to living space and the boiler room. The rest of a residential building does not require fire caulking. You will be required to provide draft stopping, but that product and method is considerably less expensive.
 
For UL System listings, go to this page, and in the box next to "Through-Penetration Firestop System", enter your search parameters:

http://database.ul.com/cgi-bin/XYV/cgifind.new/LISEXT/1FRAME/gothernbr.html

You can see the instructions here if you scroll down to "Numbering System"; you'll want to enter F, W, or C, followed by a hyphen, the second letter. another hyphen, and then 3* for all of the electrical penetrations:

http://database.ul.com/cgi-bin/XYV/template/LISEXT/1FRAME/showpage.html?name=XHEZ.GuideInfo&ccnshorttitle=Through-penetration+Firestop+Systems&objid=1074338240&cfgid=1073741824&version=versionless&parent_id=1073995580&sequence=1

Search through each of the files there for compatible brands of construction, fire caulking and cable types. It's a bit of reading, but look for a brand your local supplier carries.

Here's an example:

http://database.ul.com/cgi-bin/XYV/...n=versionless&parent_id=1073995580&sequence=1
 
Pierre C Belarge said:
If you mean fire caulk the plates in a residential buildings, you most likely do not need to fire caulk most of those holes. Most residential buildings only require fire caulking where the garage is next to living space and the boiler room. The rest of a residential building does not require fire caulking. You will be required to provide draft stopping, but that product and method is considerably less expensive.
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I do believe they are required to be fire caulked...
 
Here the building inspector doing the insulation inspection prior to drywall requires that all penetrations through the top plate be fire caulked/foamed.Used to be just foamed but around 04 they changed the requirement to fire caulk/foam.
 
stickboy1375 said:
I do believe they are required to be fire caulked...
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Not by any national code.

Most penetrations of NM through plates of wood frame dwelling construction do not need true 'Fire Caulking' products.

Expanding foam can be used if it is not harmful to the NM.
 
stickboy1375 said:
I do believe they are required to be fire caulked...
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In CT it's a state requirement to use fire caulk. Not so in MA, RI and elsewhere. Regular foam will do, as it's only to stop cold air from getting into the walls.
 
The truth is you can not make a non rated assembly any more fire resistant by using a true Fire caulk on a penetration, draft stopping is sufficient.

It seems as though there is a belief that fire caulking applied to a flammable piece of wood changes it to a fire resistant piece of wood.

I get these visions of a burnt down house with a whole bunch of little blobs of fire caulk laying in the rubble.

Roger
 
We use " Pro Great Stuff " in the orange can which has UL listing and is an approved fire blocker. For years they made us all use "RockWool" as the only method until I took a can of this stuff down to them and WHAMO....now everyone uses it around here.

Can do 3 houses on a single can......we buy it by the case with a few extra guns and it is awesome. They started making it orange so it would stand out to AHJ's.

I get my helpers to go around and fill all holes they see when we finish a rough in, even plumbers holes if they are open where we do it....keeps good relations..:)



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