# "Existing" NM above a drop ceiling?



## steveray (Sep 13, 2021)

Chris Kennedy special here..  ..Existing Restaurant coming in for an extensive remodel. Assumedly has a bunch of NM that was legally installed (pre-2005 ish)...When/ do you make them upgrade? If the take the ceiling down and replace it? When they take the ceiling and all of the lighting down? Never, just no new? Chang of use?

This might be a little IEBC and NEC, but has more to do with the sparkies I believe....


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## Beniah Naylor (Sep 13, 2021)

Main issue is that the NM cable is not plenum rated, so may cause bad fumes? How is it supported? Is the air in the above ceiling space going to be circulating in the building?

Maybe on change of use, maybe never if they don't install new. If the building is Type V construction, I wouldn't worry too much about it. I have bigger fish to fry, lol.


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## fatboy (Sep 13, 2021)

Does the work area involved include the drop ceiling?

Then I would say yes.  

Should you choose to go  there, from the IBC:

[A] 101.4.7 Existing buildings. The provisions of the
International Existing Building Code shall apply to matters
governing the repair, alteration, change of occupancy,
addition to and relocation of existing buildings.

Sends you to the IEBC, adopted or not. 

I think Section 302 can get you there.


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## steveray (Sep 13, 2021)

Here is what I sent to the contractor:

Mike,
Kicked it around and I don’t think we would be looking to get rid of the NM cable (assuming it was legally installed) unless:

it was in an area that never had a ceiling before (so it would be “like new”)
A change of use that brought in assembly or health care (IEBC 1008)
Level 2 or better work in assembly A1,2,5; H ; or I uses per IEBC 808.2
For number 3, just have the electrician look at NEC 518 (518.4B in particular) and make sure nothing jumps out at him….But NM should be OK if the construction is not fire rated…Basically if it is allowed based on use it gets to stay, ceiling doesn’t play into it…


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## chris kennedy (Sep 14, 2021)

steveray said:


> Chris Kennedy special here..  ..


Lol
Just because you don't see me post often on here don't ever think I'm not always watching


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## jar546 (Sep 14, 2021)

Look at the date stamped on the NM cable.  It always has a MFG date.  If the date if AFTER the code change that disallowed NM above a drop ceiling in a commercial building, it must be removed because it was not legally installed or the inspector was incompetent if there was a permit back then.  Bottom line, you can't "grandfather" something that was not code compliant the date it was installed.


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## steveray (Sep 14, 2021)

Exactly...we have a small window at the end of 2005 where it was legal still, yellow throws up a red flag, but not always a certainty....


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## jj1289 (Sep 14, 2021)

If the NM was "legally" installed and they are not changing it, it can remain. Had this with a Dunkin renovation. The NM above the ceiling was permitted when installed, they changed the ceiling and installed new lighting. All new wiring had to comply with the currently adopted NEC


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