What's the correct method & type of wire to go from inside (ie. basement) to an exterior, surface mounted outlet box?
The most common way I see is have an NM-B cable go from inside, through a wall (possibly in a small stub of conduit), and directly into the exterior, surface mounted outlet box. In this situation, the NM-B cable is only used in dry locations and is allowable by code.
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However, my basement doesn't extend very far above the ground level. This means that an LB fitting + conduit have to be used in order to get the exterior outlet box up to a reasonable height off of the ground. Isn't this conduit on the exterior now considered a raceway in a wet location, meaning inside the conduit is now considered wet and NM CANNOT be used? If NM can't be used in this situation, how do you get around it? Sure, you could run individual THHN wires out to the box, but then you need conduit running inside to a junction box where you can convert to NM to run back to your panel - this seems more messy than it should be.
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The most common way I see is have an NM-B cable go from inside, through a wall (possibly in a small stub of conduit), and directly into the exterior, surface mounted outlet box. In this situation, the NM-B cable is only used in dry locations and is allowable by code.
However, my basement doesn't extend very far above the ground level. This means that an LB fitting + conduit have to be used in order to get the exterior outlet box up to a reasonable height off of the ground. Isn't this conduit on the exterior now considered a raceway in a wet location, meaning inside the conduit is now considered wet and NM CANNOT be used? If NM can't be used in this situation, how do you get around it? Sure, you could run individual THHN wires out to the box, but then you need conduit running inside to a junction box where you can convert to NM to run back to your panel - this seems more messy than it should be.
