Does anyone know specifically how to construct or detail the installation of an electric Panel in a Garage wall (facing into the garage) shared with the dwelling space? Or a resource to use for such?
I understand that code requires such an install to be fireblocke on “five sides”. Obviously you have drywall on the backside of the panel on the insdie fo the house. Not sure this counts as one of the five sides or if that drywall needs to be doubled up. Then I would think you would need blocking about and below the box and that covered by drywall ??????? ASS-U_ME. And then what are details for drilling through all of this for teh wires?
Any resource suggestions? Thank you.
Yes, I could ask the inspector, but they are typically intereted in getting you to the code and not explaining the How? I fully understand this and accept it. Thanks.
Replies
Where are you?
I have never seen that in Florida or Maryland.
Where am I?
Idaho,
When I installed my service enterance and meter base last fall I told my inspector of my plan to have my panel in the garage and he said "oh .. well ... there was is five sided fire stop rule" or words to that effect. I think I asked him for specifics or information about the code and he said "you can get code info , but not answers to HOW". So where do I get the HOW?
Box in the panel.
Build a box where the panel will go with 2x blocking. Line it on 4 sides and the back with 5/8 rock. Caulk all penetrations with fireproof caulking. This is probably what they want.
I would want a cite of the code. That will let you know what you need.
I doubt NFPA even lists a 5 sided fire rated assembly but who knows. It is a thick book they want $100 for.
Code book.
I've got the latest NEC handbook. I'll see what is in it this evening.
Like you, I can't recall such a requirement in any of the code classes I've taken except for some commercial applications, but that is usualy handled with a rated enclosure, not fire blocking. Fire blocking in residential construction< IIRC, is a function of wall height and framing type,
I don't think this is an electrical code issue. Building Codes require a 1 hour fire wall between the garage and house. Any penitration of that barrier must be addressed whether it is an electrical box or something else. A 1 hour wall requires 5/8" type X rock on the garage side and framing members no more than 16" oc. (I've never seen 5/8 rock that wasn't type X.) So it seems to me that this is how the issue needs to be handled.
There is nothing in the NEC about this. I also do not see it in the ICC residential code. It has to be a local code requirement.
Thanks very one.
Not sure we have a diffenitive answer, but all very good information.
One of you guys said to build the box and block and sheet rock all five sides. That is what I would think, but not sure the one layer of sheetrock on the inside of the wall counts as typically a firerated wall has 1/2 inside and 5/8 on the garage side. ?
Someone mentioned the 1 hour rating. If you have a panel box in the wall do you loss the 1 hour rating? I would think so unless you some how add a second layer of sheetrock and block above and below (no big deal).
Someone said they thought this was a building code issue and not an electrical code issue. The interesting thing here is that it was the electrical inspector that told me about the "requirement". Perhaps he was being nice and stepping out of his field. (Then again there are not building code requirements in my county (yes , electrical but no structural). But this inspector does inspect in the county to the south and he may be very used to that issue coming up.
I am at least thinking this through.
Thanks everyone
Here's another worthless suggestion from me.
Put up a sheet of drywall, then the box. Run your service entrance from the disconnect to the box. Overhead if you wish, come straight down into the box.
Complete the wiring.
The inspector will want all the romex covered (unless you use conduit to junction boxes in the garage attic). Since the box has 5/8's behind it-you shouldn't need more drywall over the wiring. It's firetaped/fire caulked at penetrations. A simple covered wood box should suffice (it did here 23 yrs ago. Make it so it can be unscrewed to access side/bottom/top of panel later for future wiring. Include a capped conduit from panel to a junction box in attic for future pulls (and you won't have to remove the box).
or not.
Does your description ...
Does your description assume the box is attached TO the garage wall or embeded in the wall. You mention 5/8 drywall behind the box, which would be true if the box were mounted on the wall but not necessarily if it were mounted in the wall (flush mount). I prefer to flush mount.
On the wall.
but if you box around it-then it's in a space that protrudes from the wall with the box cover flush to that space.
If you add 5/8's to the back of the box (for a builtin)-you might find it sticks out if the depth of the panel box is 3-1/2" deep.
Forget I suggested it-it is a garage.
This is what the ICC says about "fireblocking" but I still do not understand how it applies to a 5 sided box.
Doesn't a panelboard fire usually shoot out away from the front of the panel
View ImageR302.11 Fireblocking.
In combustible construction, fireblocking shall be provided to cut off all concealed draft openings (both vertical and horizontal) and to form an effective fire barrier between stories, and between a top story and the roof space.
Fireblocking shall be provided in wood-frame construction in the following locations:
View Image1. In concealed spaces of stud walls and partitions, including furred spaces and parallel rows of studs or staggered studs, as follows:
View Image2. At all interconnections between concealed vertical and horizontal spaces such as occur at soffits, drop ceilings and cove ceilings.
View Image3. In concealed spaces between stair stringers at the top and bottom of the run. Enclosed spaces under stairs shall comply with Section R302.7.
View Image4. At openings around vents, pipes, ducts, cables and wires at ceiling and floor level, with an approved material to resist the free passage of flame and products of combustion. The material filling this annular space shall not be required to meet the ASTM E 136 requirements.
View Image5. For the fireblocking of chimneys and fireplaces, see Section R1003.19.
View Image6. Fireblocking of cornices of a two-family dwelling is required at the line of dwelling unit separation.
View ImageR302.11.1 Fireblocking materials.
Except as provided in Section R302.11, Item 4, fireblocking shall consist of the following materials.
Are fireblocking and fire rating getting confused? The five side fireblocking would be the studs on either side, the top and bottom plate and the drywall on the house side. The penetrations through the top plate, bottom plate and the studs would need to be sealed.
That is why we really need a code cite.
Fire stopping, fire blocking and draft stopping are completely different things. Fire stopping is an engineered assembly, draft stopping is a squirt of foam and fire blocking is somewhere in between. We need to know what they really want.
It sounds like me that a flush mounted panelboard enclosure backed up to a sheet of 1/2" drywall (from the wall on the other side), with a 2x4 across the bay on top and bottom is fire blocked. Isn't that the sole plate and the top plate?.
If this is sharing that wall with dwelling space you need another layer of drywall if they really want 1 hour but the Florida code (ICC) says 1/2" of drywall is OK, unless it is the garage ceiling with habitable space above (then 5/8)
That is why we really need a code cite.
Fire stopping, fire blocking and draft stopping are completely different things. Fire stopping is an engineered assembly, draft stopping is a squirt of foam and fire blocking is somewhere in between. We need to know what they really want.
It sounds to me that a flush mounted panelboard enclosure backed up to a sheet of 1/2" drywall (from the wall on the other side), with a 2x4 across the bay on top and bottom is fire blocked. Isn't that the sole plate and the top plate?.
If this is sharing that wall with dwelling space you need another layer of drywall if they really want 1 hour but the Florida code (ICC) says 1/2" of drywall is OK, unless it is the garage ceiling with habitable space above (then 5/8)
We would need to know what version of the Code is being used in Idaho and is this a residential or commercial application.
Gfretwell, I'm disappointed in your replies ... surely you can do better!
Here's the deal ...
The wall between the garage and the dwelling is often required to be a 'firewall' with a certain (say, 2-hr.) rating. You're not allowed to do anything that will reduce that rating.
There are a variety of resources out there - the US Gypsum "Gypsum handbook,' available free at their web site is one such reference- that describe specific wall assemblies in detauil, along with their ratings. What you do is figure out which stock plan represents the wall you have, then follow the design specifications for making changes to that wall.
Since most designs seem to rely on the simple thickness of the drywall, is is a common approach to make a drywall 'box' to surround things like electric panels. The idea is that this will technically place the panel 'outside' the wall. As usual, the devil is in the details - especially how the wires pass through the barrier. It's hard to properly seal these holes with joint compound, and a wall full of holes is no wall at all. That's why there are all sorts of caulks and foams made for this use.
Personally, I'd dodge the issue completely, and just mount the panel on the surface of the wall. There's no reason you can't also 'box in' the wires if you don't want to see them.
I guess I just live in a place that doesn't go nuts about the garage.
View Image
I agonized over this crap a few years ago.
I put my 200 amp panel on the short wall next to garage door. Main wall of the house is 5/8" drywall. Seal wire holes with "red fire caulk". it passed. Coax / phone box and some garage outlets are in a 2x4 frame wall against the 5/8" drywall of the main 2x6 wall.
I tried to get simple questions answered such as can U even run (2) "romex" cables thru 1 hole in wood framing? What about 3?
Codes becoming more an d more retarded every day making it so you cannot work on your own house. Everything I do on my 2 rental shacks is illeagal because U have to sign an affidavit to get any permits that says U will live there with your crappy work for 2 years B4 subjecting the "normal" populace to your sub-std work! I'm not bitter though.