Use of Remex

Toros

Senior Member
Location
Tujunga, CA
Hi, I am confused would somebody explain me the type of construction and use of romex, NMC permitted in those type of constr. Example: can a 1-story building , non-sprinklered used as a restaurant be wired through romrex?????? Thank you
 

hurk27

Senior Member
Hi, I am confused would somebody explain me the type of construction and use of romex, NMC permitted in those type of constr. Example: can a 1-story building , non-sprinklered used as a restaurant be wired through romrex?????? Thank you
Not sure if it could be in Ca. but here it could as long as one single room or separate area doesn't have seating for more then 100 people at a time, and that is even if a sprinkler system is required, here fire sprinklers are required anytime a commercial building exceeds 5k,sf, many of the chain hotels around here some 5 stories are all NM, just meeting rooms with capacities over 100 people or if they have a stage are required to be in pipe.

But Ca. may be different.

Also remember no NM over suspended ceilings in commercial

The NEC allows NM in type III, IV, and type V construction see 334.10,and also see Annex E Types of Construction in the back of the NEC.

It really has nothing to do with being residential or commercial, at least here it doesn't.

Here it can depend on if the state rates a building a I, or II type construction for most part if only a 15 minute barrier is required NM is good to go, but for a little better understanding take a look at Annex E Types of Construction in the back of the NEC, and then check to see if Ca. follows these guide lines.

Most schools will be of a type I or II rating, the hotels I mentioned had a type III, but if over 5 stories here it jumps to type II, most homes or multi-family are type V with a few large apartment buildings that can be type III if under 5 stories, or type II if over this, a log cabin type home is a type IV and it is considered heavy timber construction. but as Indiana has changed some requirements Ca. may have also.
 
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GoldDigger

Moderator
Staff member
Since the NEC states the permissions for NM based on building construction type, you need to look at the definitions of those building types elsewhere, such as in building codes.
Some readers (like me) further base the classification on the building construction type allowed for a type of occupancy rather than the type of construction actually used.
The situation gets really sticky when an existing single family residence, for which any construction type is allowed gets converted to another use. Does the whole building then need to be rewired to remove NM or do you at least have to see whether NM is allowed for new wiring.

Tapatalk!
 

hurk27

Senior Member
Since the NEC states the permissions for NM based on building construction type, you need to look at the definitions of those building types elsewhere, such as in building codes.
Some readers (like me) further base the classification on the building construction type allowed for a type of occupancy rather than the type of construction actually used.
The situation gets really sticky when an existing single family residence, for which any construction type is allowed gets converted to another use. Does the whole building then need to be rewired to remove NM or do you at least have to see whether NM is allowed for new wiring.

Tapatalk!
I was editing my post when you posted, but the NEC does not differentiate the type of occupancy or residential or commercial, church or bar, hotel or apartment, 334.12 has some restrictions to those other types of occupancy's but only for things like no NM above suspended ceilings, Stages, places of assembly (100 or more people in one room) even then the rest of the building can be NM 518.4(B).
 
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infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
Hi, I am confused would somebody explain me the type of construction and use of romex, NMC permitted in those type of constr. Example: can a 1-story building , non-sprinklered used as a restaurant be wired through romrex?????? Thank you
Just curious as to where did you find this question?
 

Toros

Senior Member
Location
Tujunga, CA
Hi, I am confused would somebody explain me the type of construction and use of romex, NMC permitted in those type of constr. Example: can a 1-story building , non-sprinklered used as a restaurant be wired through romrex?????? Thank you

From deep - in-my
heart
Mr Rob
 

GoldDigger

Moderator
Staff member
If the reason that the one story restaurant building does not need sprinklers is that it is of all concrete and fireproof wall (metal stud and gypsum wallboard) construction, then you are not allowed to use NM, just as one example.

Tapatalk!
 

augie47

Moderator
Staff member
Location
Tennessee
Just a point:
Wording can be very important in the NEC. In that light::::::
In your original post you used the term Romex and NMC.
The NM-B cable most of us use today is commonly called Romex although "Romex" is a brand name
FYI: (from Southwire)
The History of Romex[SUP]?[/SUP]
The Romex[SUP]?[/SUP] brand of Non-Metallic Building Wire (?NM?) originated in 1922 with its development by the former Rome Wire Company, a predecessor to General Cable Corporation. On September 5, 2001, Southwire purchased the electrical building wire assets of General Cable Corporation. One of the most valuable assets purchased by Southwire in that acquisition was the Romex brand of Type NM cable. The Romex brand of Type NM cable has now been promoted and sold by Southwire and its predecessors for 88 years and Southwire considers its Romex trademark to be one of its most valuable brand names. Romex is a federally registered trademark and we vigorously monitor and protect the use of the Romex brand in North America and around the world.


In regard to your post, NMC and NMB have different characteristics and uses. I doubt you will find any "NMC" available, however, UF cable can normally be used where NMC would be required.

Thats all I have from the worthless information file at the moment
(please don't confuse me with guru :) )
 
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Sierrasparky

Senior Member
Location
USA
Occupation
Electrician ,contractor
Romex should be allowed , Romex is even allowed in Beverly Hills these days.

CA law requires the following of the current building codes in CA only , A dept can only Restrict or modify a code based on Climatic , topographical and I think seismic.

I don't think there are too many instances where that would apply to romex in CA.
 

kwired

Electron manager
Location
NE Nebraska
Romex should be allowed , Romex is even allowed in Beverly Hills these days.

CA law requires the following of the current building codes in CA only , A dept can only Restrict or modify a code based on Climatic , topographical and I think seismic.

I don't think there are too many instances where that would apply to romex in CA.
But NM is not allowed in Chicago.

From early in my career this debate has always bugged me. Why NM cable is not allowed in many public access buildings? We tend to think it is unsafe, and will cost lives in places where people are either awake and alert, or at least there is enough people around to alert others if there is a problem, plus there generally fire alarms or fire suppression involved for additional safety.

But there is nothing wrong with using NM cable in our homes where we sleep at night without as many possibilities in general to alert us if there is a problem:( Then we come back and say there maybe is a problem with NM in the dwellings and throw AFCI's at it as a solution, I would rather see a ban of NM cable altogether and forget the AFCI's.
 

Sierrasparky

Senior Member
Location
USA
Occupation
Electrician ,contractor
But NM is not allowed in Chicago.

From early in my career this debate has always bugged me. Why NM cable is not allowed in many public access buildings? We tend to think it is unsafe, and will cost lives in places where people are either awake and alert, or at least there is enough people around to alert others if there is a problem, plus there generally fire alarms or fire suppression involved for additional safety.

But there is nothing wrong with using NM cable in our homes where we sleep at night without as many possibilities in general to alert us if there is a problem:( Then we come back and say there maybe is a problem with NM in the dwellings and throw AFCI's at it as a solution, I would rather see a ban of NM cable altogether and forget the AFCI's.
There are a lot of things that are different in other states.
NM used to be outlawed in many localities in California. The state passed a law that prohibits a more restrictive code than the state has adopted unless certain substanial requirements have been met.
 

kwired

Electron manager
Location
NE Nebraska
There are a lot of things that are different in other states.
NM used to be outlawed in many localities in California. The state passed a law that prohibits a more restrictive code than the state has adopted unless certain substanial requirements have been met.
That is opposite of the way it is here. Cities/counties that have their own inspection programs can make amendments that are more restrictive than what the State is enforcing (which in recent years has been strictly NEC content with no amendments) but cannot make amendments that are less restrictive.
 

Sierrasparky

Senior Member
Location
USA
Occupation
Electrician ,contractor
That is opposite of the way it is here. Cities/counties that have their own inspection programs can make amendments that are more restrictive than what the State is enforcing (which in recent years has been strictly NEC content with no amendments) but cannot make amendments that are less restrictive.
That is similar to Calif. Localities can make more restrictive but never less restrictive.

The more restrictive changes must meet certain requirements though.


Any city, county, or fire protection district may establish more restrictive building standards than those contained in the California Building Standards Code (California Code of Regulations, Title 24), if the amendment is reasonably necessary because of local climatic, geological, or topographical conditions
 
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