Romex

[wrestlesss1]

What type of insulation is on the individual Conductors in Romex ? If it is in fact THHN why wouldn't they use THWN and eliminate all the nonsense, of using UF inside a 10ft sleeve of PVC ,on exterior of house. I had one Inspector tell me that the LB (pvc ) was considered a damp location. I get it but! If they used THWN in Romexwould this not comply with NEC ? I mean the plastic jacket has no bearing on the individual Conductors.

 

[infinity]

NM cables are required to have 90°C conductors. They are not marked and not required to be insulated with a particular insulation type. The inside of a raceway on the outside of a structure is a wet location so NM or the individual conductors contained within the NM cable cannot be used in that raceway.

 

[don_resqcapt19]

If they used THWN in Romexwould this not comply with NEC ?

It is also a product standards issue...before the NEC can change you would have to get a change in UL 719, "Nonmetallic-Sheathed Cables."