Mounting boards for panels

Status
Not open for further replies.
M

MR. S

Member
Location
Connecticut
Many inspectors want the mounting boards for panels to be painted with high temperature paint or use fire rated plywood, in commercial and
residential applications.I cannot find anything in the NEC, so I am assuming this is a building code. Am I correct, or you know what they say If you assume......................... MR. S.
 
paint

paint

More than likely its a "we've always done it that way" especially in residential applications, but in many commercial applications it will be called out in the elec. spec's.:grin:
 
Why would you need one piece of fire resistant plywood in a house made of 2x4's and plywood??

I think those inspectors are off their rocker!!

Steve
 
Steve and John I agree. The applications that require fire retardant material is in certain occupancy and type classifications of construction. Also, there are IBC provisions that would call for fire retardant treated wood on an exposed platform and the space below which is used for equipment, wiring, plumbing does not have to be fire retardant treated wood. IBC 410.4 Must be a local AHJ thing.
 
steve66 said:
Why would you need one piece of fire resistant plywood in a house made of 2x4's and plywood??

I think those inspectors are off their rocker!!
Click to expand...



j_erickson said:
Do they make you use fire rated lumber for every box you mount, too?
Click to expand...


Probably the same reason you can't install a panel in a closet...? I'm required to paint my panel boards with fireproof paint also, its BS if you ask me, but I don't buy pressure treated plywood either so it resolves the issue of mounting CDX to concrete.
 
Last edited:
stickboy1375 said:
Probably the same reason you can't install a panel in a closet...? I'm required to paint my panel boards with fireproof paint also, its BS if you ask me, but I don't buy pressure treated plywood either so it resolves the issue of mounting CDX to concrete.
Click to expand...

That is the reason that I have always done in, basically to give the plywood some moisture protection and seal it so there is less chance of deterioration over the years. You bring up an interesting thought about the pressure treated plywood though........does anyone use PT plywood to mount their panels on? I would have concerns with that with what kind of effect it would have on the metal panel. I know that you have to use the specified fasteners when installing PT wood, on decks for example as it will eat right through regular screws and or nails.
 
Interesting, I never heard using specific screws on PT wood, good to know.
To get around the moisture issue, I like to shoot two 2X4's flat onto the
concrete, screw my plywood to that, then I have an air space between my
plywood and concrete, and a chase behind my panel to run wires into the
bottom of the panel if need be. MR. S
 
What do these inspectors want you to do if you are using a flush mount loadcenter?

Roger
 
Some time ago an EC in this area got his you-know-what in a sling because he was mounting panel boards on plywood onto concrete walls. The claim was that the plywood was flammable. I am not sure what the issue was exactly, maybe non-flammable materials required.

I gather that this was a common practice and was being passed by the inspectors.

Somehow he ended up getting additional scrutiny beyond what the other ECs got (I think I know why but it is not relevant) and ended up having to make a fair number of them non-flammable by painting them with some kind of coating. They even made him go back and redo a bunch of them that they had already passed, or so i was told.
 
It seems silly to ask for a high temp. paint on a flammable board. So the paint doesn't burn but the board does? This makes no sense to me, the panel it self is not what you would consider combustible. To much "what if " thinking with this inspector. If you put a piece of sheet metal behind the panel would they still make you paint the board behind the sheet metal?
When we installed mutiple panels in telco sites they wanted us to use a continous sheet metal surface on 3/4'' ply to mount all the equipment to.Also bond it to the "grounding window" as they called it. It made for a pretty finish but I doubt it made much of a differance. It was not for fire rating to them it was for additional bonding above and beyond the conduits and egc in the boxes.
 
acrwc10 said:
It seems silly to ask for a high temp. paint on a flammable board. So the paint doesn't burn but the board does? This makes no sense to me, the panel it self is not what you would consider combustible.
Click to expand...


Then why not legal to install a panel in a clothes closet?
 
MR. S said:
Interesting, I never heard using specific screws on PT wood, good to know.
To get around the moisture issue, I like to shoot two 2X4's flat onto the
concrete, screw my plywood to that, then I have an air space between my
plywood and concrete, and a chase behind my panel to run wires into the
bottom of the panel if need be. MR. S
Click to expand...

I do pretty much the same. I always mount 2x4's or 2x6's to the concrete with nailers and plywood to the 2x's. Actually I try to hang my 2x's from the joists when the situation allows. Then plywood hangs 3" down from the joists, even with the top of concrete foundation. There is always at least the 3 1/2" space between the plywood and concrete. I've never once mounted a piece of plywood to the concrete wall. But I see a lot of guys who do.
 
stickboy1375 said:
Then why not legal to install a panel in a clothes closet?
Click to expand...


With the size of some of the closets I have seen "huge'' I don't think it should be prohibited if the closet is over a certain size. I worked on a house last year where the master closet was larger then the kids bedroom.
 
Status
Not open for further replies.
Top