ampacity of general lighting and outlet conductors

[brucestart]

Recently I started a a project where an old bank biult in the early 50's is being transformed into a show room with some office space and an apartment on the top floor. I always thaught that as a requirement I had to run 20 branch circuits for general lights and outlets in banks and offices but I can't find any reference in the code stating that these circuits cannot be 15 amp circiuts. The biulding is 3 stories and wood framed construction, is there any reason why these loads cannot be suplied by 15 amp circuit using 14 gauge romex? Please site any code references.

thanks, Bruce

 

[pierre]

Re: ampacity of general lighting and outlet conductors

Some local jurisdictions have restrictions only allowing 12 awg conductors as the minimum size in commercial spaces, the NEC does not have this restriction.

Pierre

 

[david]

Re: ampacity of general lighting and outlet conductors

From your post you seem to be asking about the office area, but you also said you are wiring an apartment on the top floor.

The two or more small appliance circuits the bath room receptacles and if you put a laundry room these circuits would all be required 20 amp.

 

[bob]

Re: ampacity of general lighting and outlet conductors

Bruce In your post you said "I always thought that as a requirement I had to run 20 branch circuits for general lights and outlets in banks and offices". I think you ment to say 20 amp circuits. Table 220.3A requires banks to have
3.5 va per sq. ft for lighting an 1 va per sq. ft for receptacles. I don't think the code will
stop you from installing 15 amp circuits. In commercial buildings you will usually find 20 amps circuits. How much difference in the cost.

 

[bob]

Re: ampacity of general lighting and outlet conductors



[ July 13, 2003, 11:29 PM: Message edited by: bob ]

 

[hbendillo]

Re: ampacity of general lighting and outlet conductors

15-amp circuits and #14 NM cable sounds OK to me. Make sure that you look at the code on restrictions for use of NM cable especially in the showroom and office part of the facility. I do not think you can use NM cable above suspended acoustical tile ceilings.