I need to rewire an outdoor box for camera + light and I will have the cable go from inside the house directly into the box outside. IOW, the point where it exits the house will be directly the point where it enters the box, so the cable will not be exposed outside. The box is weather proof, ie should not leak because it has a gasket.
Do I still need to use outdoor grade cable or can I just use regular Romex NM?
Best Answer
It's commonly done and gotten away with.
But. It's also wrong - Any outside box or conduit should be treated as if it will be full of water - even "perfectly waterproofed" things will fill up with condensation, unless you go to the bother of pressurizing them with dry gas and maintaining that dry gas pressure.
Code is clear on outside conduit, perhaps less so on outside boxes not fed by conduit, which might be why it's gotten away with in terms of inspections.
Have some delivered, or go to the store.