Panel enclosure fire rating

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I have an existing panel in a chase wall. Does the panel enclosure provide a specific fire rating or do I need to wrap it in gypsum. I have been told that once I go into the chase I have to bring it up to current code including adding fire dampers on the ducts, sealing all holes with fire seal etc.:).
 
pator said:
I have an existing panel in a chase wall. Does the panel enclosure provide a specific fire rating or do I need to wrap it in gypsum. I have been told that once I go into the chase I have to bring it up to current code including adding fire dampers on the ducts, sealing all holes with fire seal etc.:).
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Welcome to the forum. What is the current NFPA rating of the wall that the chase is in?
 
If your wall is actually rated, then you cannot install the panel in it with out wrapping it. Since panels exceede the 16 sq ins of allowed opening, it would be very expensive to build one that was 1 hr rated.
 
If you are truly dealing with a Fire Rated Wall then forget putting the panel enclosure in it. Move it outside of the rated wall either in a false wall build on top of the rated wall or consider moving the location all together.

You will be hard pressed to find a local AHJ that will approve it...I know we would not.
 
radiopet said:
If you are truly dealing with a Fire Rated Wall then forget putting the panel enclosure in it. Move it outside of the rated wall either in a false wall build on top of the rated wall or consider moving the location all together.

You will be hard pressed to find a local AHJ that will approve it...I know we would not.
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Good to hear from you Paul
 
The old wrapping the panelboard cabinet in drywall trick has been around forever. In the old days it was state of the art considering the industry at the time.

I agree with Paul because this drywall wrap method has never been tested by anyone, that I know of.

3M does have a firestop system that is close. Your AHJ MIGHT approve an engineering judgement based on it. We MIGHT consider it if the panelboard cabinet was existing and the wall was being upgraded to one hour fire resistive. For a new installation - just say UL classified firestop system please.

http://database.ul.com/cgi-bin/XYV/...n=versionless&parent_id=1073995580&sequence=1
 
pator said:
I have an existing panel in a chase wall. Does the panel enclosure provide a specific fire rating or do I need to wrap it in gypsum. I have been told that once I go into the chase I have to bring it up to current code including adding fire dampers on the ducts, sealing all holes with fire seal etc.:).
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To answer your question more directly, it's up to your AHJ.

I personally would not make you start upgrading everything in sight just because you did one little thing.

Someone probably approved what is existing and it may have even been code compliant at the time.
 
Does this mean that you cannot install a flush mount subpanel in the wall between a house and an attached garage?
 
gary said:
Does this mean that you cannot install a flush mount subpanel in the wall between a house and an attached garage?
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Not necessarily, the separation in a single family dwelling between an attached garage is only 1/2" gypsum. The openings between the garage and dwelling such as the door are only required to have a 20 minute fire rating.

As long as the panel in the wall is rated for 20 minutes or more and is properly sealed, this is never a problem. There are some plastic device boxes that have over a 1 hour fire rating.

If sub panels were not allowed in this area then neither would switches and receptacles.

You can install devices and panels in the wall between a garage and dwelling if properly rated (most are) and installed.
 
I am in the process of getting an EJ on using 3M's mat.

On the particular project there are 17 flush mount panels in 2-hour corridors.

EE said 'huh?', arch said 'huh?', I said I told you so.

The problem is there is only 3/4" between the back side of the panel and the rock on the other side.
 
ivsenroute said:
Not necessarily, the separation in a single family dwelling between an attached garage is only 1/2" gypsum. The openings between the garage and dwelling such as the door are only required to have a 20 minute fire rating.

As long as the panel in the wall is rated for 20 minutes or more and is properly sealed, this is never a problem. There are some plastic device boxes that have over a 1 hour fire rating.

If sub panels were not allowed in this area then neither would switches and receptacles.

You can install devices and panels in the wall between a garage and dwelling if properly rated (most are) and installed.
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The issue is not devices installed in these walls.

The issue is that you are limited to a 16 sq. in. opening.
 
walkerj said:
The issue is not devices installed in these walls.

The issue is that you are limited to a 16 sq. in. opening.
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The 16 sq. in. does not apply to separation between the garage and the dwelling, only for the membrane penetration (one side) between dwelling units such as townhouses or 2 family units where a 2 or 1 hour separation is required depending on whether or not the units are sprinklered.

As long as you maintain the 20 minute fire rating of the membrane penetration between the garage and dwelling which would include fire-blocking and flame and smoke spread under ASTM E-84, there is not a problem installing a panel in that wall between the garage and dwelling.

Commercial construction and fire rated assemblies are of course more restrictive.
 
ahh......they do make switch boxes that are rated to be in a rated wall. We do have requirements in the IRC and IBC that govern this, limit the size of the openings and so on.
 
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Or..maybe I should say that the jurisdictions I have worked in would not allow it in the seperation wall. Again others might disagree so i am just giving you my opinion on what AHJ's I have worked with would not allow.
 
but honestly....I dont believe anything in the IRC would prohibit it but I think the USBC does on the inside wall of the garage. Just know that many local AHJ's don't want it. I dont have my USBC or IRC handy.....so I can't check.
 
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