whats the issue with this.. i thought i remembered a while back there was a code which said your panel has to be mounted on the black plywood.. certain size etc.. but than i thought i heard it was removed.. where can i find more info on this.. and is it a special paint which the plywood is coated with? where in the code would this be located?
Black plywood for panel mounting
- Thread starter tataco84
- Start date
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peter d
Senior Member
- Location
- New England
It's not an NEC requirement but I believe New Jersey has a state requirement for it. Check your local codes.
kenman215
Senior Member
- Location
- albany, ny
Never heard of having to use painted plywood before, but we use fire-rated plywood over Sheetrock walls all the time.
JFletcher
Senior Member
- Location
- Williamsburg, VA
- Location
- Simi Valley, CA
There is a fire resistive paint.
mgookin
Senior Member
- Location
- Fort Myers, FL
- Occupation
- Retired inspector, plans examiner & building official
Lots of things come into play.
In building construction types we have allowable building materials and fire resistance ratings for structural elements.
Then we have allowable building materials and fire resistance ratings for non-structural elements including partitions (walls).
Then we have interior finish classification based on occupancy classification and what portion of that occupancy you are in (exit access vs restroom, for example). Interior finish classification is a function of the flamespread and smoke development characteristics under ASTM E84.
Then you have the fact that it's not wise to try to surface mount a panel on a sheetrock wall without something to bite on to.
So there's a whole lot to it.
In all my years I can't say I've ever seen a requirement for black or even seen black in the field. It makes sense to paint it black so that 20 years later it looks better than it otherwise would.
My suggesting is to use FRT rated (fire rated treated) plywood whenever you need a plywood backer behind a surface mount panel. It's done all the time. And if your work leads to excess heat, having that FRT will be wise.
In building construction types we have allowable building materials and fire resistance ratings for structural elements.
Then we have allowable building materials and fire resistance ratings for non-structural elements including partitions (walls).
Then we have interior finish classification based on occupancy classification and what portion of that occupancy you are in (exit access vs restroom, for example). Interior finish classification is a function of the flamespread and smoke development characteristics under ASTM E84.
Then you have the fact that it's not wise to try to surface mount a panel on a sheetrock wall without something to bite on to.
So there's a whole lot to it.
In all my years I can't say I've ever seen a requirement for black or even seen black in the field. It makes sense to paint it black so that 20 years later it looks better than it otherwise would.
My suggesting is to use FRT rated (fire rated treated) plywood whenever you need a plywood backer behind a surface mount panel. It's done all the time. And if your work leads to excess heat, having that FRT will be wise.
goldstar
Senior Member
- Location
- New Jersey
- Occupation
- Electrical Contractor
To the best of my knowledge I don't know of a NJ requirement for black painted back boards. I think (way back when) there may have been a generally accepted method of mounting a breaker panel on plywood when installing against a masonry wall. I think the theory was that if the masonry wall had moisture seeping through it, that moisture would be less likely to seep into the breaker panel if it were mounted on wood and thereby held off the masonry. You'll also notice that the mounting holes on most breaker panels are dimpled and held off the mounting surface by about 1/16" to 1/8" in the event there is some seepage. There was also black "meter board paint" that was used but I don't remember the characteristics of it. In terms of appearance, a gray or tan panel looks a lot better against a black surface than it would on a plain masonry wall. If for no other reason, you'll show the EI you actually care about the appearance of your work.
Just my 2 cents worth.
Just my 2 cents worth.
PetrosA
Senior Member
- Location
- Lancaster, Pennsylvania
I haven't seen a service on black painted wood/plywood here that would have been done after the 40s or 50s. Nowadays if they're painted, it's gray.
Fulthrotl
~Autocorrect is My Worst Enema.~
- Occupation
- E
here, telco backboards need to be fire rated plywood, and can be painted,
but the fire retardant mill mark needs to be left unpainted for the inspector.
- Status