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do you like NM in commercial bldgs?

BSSTG

Gold Member
Joined
Nov 30, 2009
Messages
729
Location
Seadrift, Tx.
Greetings all,

A few years back romex was not allowed in any commercial bldg here no matter what. At some point in time that restriction was removed from the local municipal ordinance and nowadays it's ok so long as the NEC. There are some locals here that would like to see NM not be allowed in commercial bldgs whatsoever.

I've heard of various types of restrictions regarding the use of NM over the last 30 years. As for me I'm prone to just go with restrictions as per the NEC.

What do you folks think, go with the NEC or modify the NEC rules?

thanks for the input

BS
 
What I don't like about the use of NM in commercial is that it ends up above a drop ceiling when the tenant decides to add a drop ceiling.

pc1
 
I am not aware of any reports or incidents of a hazard arising due to the legal and code compliant installation of NM cable in a non-dwelling occupancy. I think you would find it hard to establish significant substantiation to change or modify your local code from the nationally recognized code allowance for NM cable in commercial occupancies when in compliance with Article 334 of the NEC. On the other hand, the opposition to such a proposal can provide many examples and evidence of installations of NM cable in non-dwelling occupanices that have been successful and are perfectly safe.

So it's really not a question of what one likes. Opinion in matters such as this is not enough to create such as change...
 
We currently have an amendment that prohibits the use of NM in commercial applications, supported by a couple old school master electricians on staff, and have the support of my advisory board. I figure if it has continued to be allowed in the body of the NEC for at least two cycles, it must be OK. Just adopted the 2011.......maybe next time they will see the light.
 
Let me rephrase. We go by the building type. If the type of construction allows combustionables then yes we allow NM. It could be a Type V commercial building and have metal studs. Being that Type V construction allows combustionable materials NM is allowed to be installed.
 
Mule, I thought that's what you meant, just checking, thanks.

We allow it here but I let them know I prefer them not to use it in commercial, NM sometimes ends up above a drop ceiling because of a contractor or owner not seeking a permit.

pc1
 
NM used to be limited to buildings 3 stories in height, and could be installed above suspended ceilings. A couple code cycles back the height restriction was removed and the suspended ceiling restriction imposed. The NEC has limited its use in assembly buildings to non-rated assemblies.

I personally think it would make the most sense to allow it anywhere unprotected wood frame construction is allowed, and maybe in 1-hour assemblies in some occupancies, such as residential or office, but the powers that be at NFPA don't want to make it that simple.
 
I'd worry more about damage to the sheathing to NM in metal studs rather than combustibility. Call me crazy.. so many electrical apprentices/laborers/the guys they find at the local big box who "know electrical" do such a fine job running it.

The problem with dis-allowing it is (well, 2).. there are several commercial buildings who have performed perfectly fine with it, and... most elected/appointed officials are not comfortable with amending national codes (particularly the NEC).
 
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