I plan on running wire from a nearby exterior GFCI AC Box to the soffits on my house for soffit lighting.

Behind the GFCI box is the garage. I was thinking about running the romex along the bottom of the siding -> In the channel of the 90 degree vertical siding "corner" and then into the soffit.


What would be the best way to run the wire from the exterior box to the soffit? Should I use conduit or is running the wire bare but in the channels of the siding good enough?

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    any surface mounted wiring must be in a conduit of some sort. It can get ugly, but if you run it below the siding and then along the corner piece to the soffit, your neighbors might not say: "yew, why did they do that!?!?!" Mar 20, 2020 at 1:22
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    ...and Romex is not exterior (wet-location) rated, so you can't use that regardless. All outside conduits are defined as wet locations, and need wire rated for wet locations. The definition is typically accurate. Unprotected along your siding is also a wet location, and also subject to damage, whic is why you need conduit (then put THWN in the conduit and the wet part is dealt with.) Or re-evaluate running directly from inside, if you don't want it to show.
    – Ecnerwal
    Mar 20, 2020 at 2:20
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    @Ecnerwal Wow, that's really interesting, because a lot of the camera work that was done around out house has the low voltage DC wire running on the siding. Mar 20, 2020 at 4:34
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    @SarahSzabo Sorry, we thought you meant AC power. Where are you going to put the low voltage transformer/supply for the lights? Is it outdoor rated? Mar 20, 2020 at 6:03
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    Romex is a company name, not a product, and they do make UV/wet-rated cable. This is why I dislike using the term "romex" as a product reference--it's ambiguous at best.
    – isherwood
    Mar 20, 2020 at 14:28

2 Answers 2


A UV resistant type of non metallic called UF (underground feeder) is allowed to be used exposed code requires the cable to be protected , above 8’ is normally considered protected by height in the national electric code. If the cable height is above 8’ it could be routed along the siding but would look like a diy hack job. Since conduit would be required for the rise to 8’ why not do the run in conduit or pull the line inside in the wall along the roof truss to the soffit and out, that would be the pro way to do it and you may have a receptacle you can tap closer, a few small holes in the drywall to patch , this would be my suggestion.

Note low voltage is not restricted as much as power.


I would seriously evaluate low voltage lighting for this task, as it will let you use cables with more liberalized rules.

However, in your case I would run PVC (yeah, take a picture, me recommending PVC!) conduit, with a conduit body exiting the bottom of the receptacle box, running just below the bottom of the sheathing... then another conduit body to turn the corner horizontally... then another conduit body to go straight up on the left side of that cap... then yet another to hug that shadowy eave, then tee's out to wherever your light positions are.

Remember to run ground in the PVC, or do the whole works low-voltage. When you use Class I wiring methods like the above, it removes the 55W limit on low-voltage (it's a bit more complicated than that, but...)

Lastly (or firstly because then you can rattle-can it), scuff-sand the PVC with a 3M Scotchbrite sponge/pad (green), then apply primer pref. alkyd (e.g. Kilz Original or Rustoleum 7780), then topcoat to match the house. That will greatly improve the camouflage, and more importantly, will protect the PVC from solar UV damage, which will tear it up in a couple of years if you don't.

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