I am bidding on a building remodel that will be an event hall on the lower level and an apartment on the 2nd floor. My question is what type of wiring method may I use on the 2nd floor apartment? I understand how article 518.4(A) applies to the event area on the main level. But, article 518.4(B) states that NM cable is permitted in "non-rated" construction. How do I make the determination as to this rating, without going to the AHJ?
"(B) Nonrated Construction. In addition to the wiring methods of 518.4(A), nonmetallic-sheathed cable, Type AC cable, electrical nonmetallic tubing, and rigid nonmetallic conduit shall be permitted to be installed in those buildings or portions thereof that are not required to be of fire-rated construction by the applicable building code. FPN: Fire-rated construction is the fire-resistive classification used in building codes."
Fire rated construction ratings are determined from the Building Codes that are adopted in your state/area.
Are there any plans? The info you need should be on the cover page of the plans. You may be able to access the local building codes on your state/local websites.
IMHO, the apt floor/assembly ceiling component will be 'rated', probably 1 hr; possibly 2 hr., but this is only my guess.
Actually now that I re-read the plans, the information is given on the cover page. It states "1 hour fire barrier as required per table 508.3.3. However, A footnote states "We will be submitting an application for variance regarding the sprinkler system and seperation requirements due to the historical architecture of the existing building". So, I am not sure. Looks like I will be contacting the Engineer.