EvaleeHunter
Thank you for your post. Some of the topics your questions refer to were covered in the additional articles I referred to. I just copied the first article in the series for this BB.
Anyway, I’ll try to answer as best I can.
Metal conduit has not been an acceptable wiring method in agricultural buildings for the last few code cycles. (Article 547, National Electrical Code, NFPA). Austensibly because metal in an environment like a barn, with high moisture content, corrosive atmosphere, and temperature variations, causes corrosion in the conduit.(Although they don’t tell us why they make the changes usually)By the way, code changes are generally not retroactive, so if it was legal when you did it you’re generally OK)
Yes, absolutely GFI outlets are required, and AFCI (Arc Fault Circuit Interrupter) circuit breakers, although not required, afford even more protection. I devoted an entire article to them, I just didn’t include it here.
Similarly, yes absolutely, wet location covers are required. I just didn’t intend for this to be a comprehensive set of instructions about how to wire a barn, merely an overview and a description of how I assess a barn electrically)
Yes, Type UF-B (“Underground Romex”) is permitted in an agricultural building> It is much tougher than the “Romex” used in houses, and my experience is that the rodents don’t usually chew it like they would “Romex”. It is required that mechanical prtection be added where the cable is subject to damage, and that, to most inspectors, means sleeving it up to a point 8’ above the floor with PVC conduit. For that reason, we just go ahead and do the whole job in PVC Conduit ususally.
Since I wrote that article, a new product has been approved for barns. It is PVC-coated MC Cable. If you think of “BX” cable that has been dipped in PVC, you won’t be too far off. It is good, but both the cable and the fittings are expensive. I would save this for those instances where conduit just won’t work, such as snaking into a wall cavity.
I hope I’ve been helpful. Like I said, I didn’t mean to cover everything but I thank you for pointing out areas where people might need more information.
I was surprised that it took so long for someone to question the metal conduit thing. When I give talks, people usually question that right away!
Tom G.
As has been said before, it’s only a job if you’d rather be doing something else.