Shop Wiring Conundrum

[Joshua Hill]

Hey guys. I've searched a few of the wiring threads and haven't found the info I need to solve my problem.

My shop is a basic two-car garage and naturally doesn't have enough 120v or a single 240v. I didn't think adding a few circuits would be much of a problem until after I bought all the materials (oops) and opened up the service panel to start pulling cables. It's mounted externally and the KO that goes from the box through the brick into the wall cavity and up into the attic is jam packed with what looks like the cables for every circuit in the house leaving no room for anymore.

The best solution I can come up with is to run the cables out of an available side KO in conduit up into the soffit. However the problem is I opened my spool of Romex, and it can't be run in conduit on account of the wet (exterior) location.

So my question is: can I run UF cables in conduit from the panel to the soffit and then splice the them into Romex cables? If so, would it be worth the extra work to do that instead of just running UF all the way to the receptacles? Thanks much for your time.

JLH

[Tim Bridge]

You are correct in that romex cannot be installed in a conduit that is outside. The interior of any conduit outside is considered a wet location. Romex, type NM-B is not suitable for a wet location.
instead of using UF cable in the conduit and splicing to romex, I would run the conduit from the panel to a box inside and use THHN wires, then splice these in the box to the romex.
This is a code compliant method.

You can use UF in the conduit and splice to the romex inside, but you will still need a box. The conduit wouldn't need to be run to the box though. The conduit could just run from the panel and stub into the soffit.

[Charles Lent]

I would put a sub panel inside and a high amp breaker in the outside box to feed it. Then wire all of the 120 and 240 circuits for the shop from breakers in the sub panel. The feeder to the mains in the sub panel could be run through that large knock out in the outside panel through conduit to the sub panel inside using wire of the right type and size for the size of the sub panel. All wiring in the garage / shop could then be done with romex IF the romex is going to be protected behind a wall covering. If the wiring will be on the surface, the code requires conduit or armored cable, so romex can not be used.

Charley

[Tom M King]

I'd put a sub panel in the garage, like Charles suggested. Wiring devices with UF is no fun.

[Malcolm Schweizer]

+1 on adding a sub panel. You'll save time and have a lot more amps to play with... Figuratively speaking, of course.

[Mike Henderson]

I'd put a sub panel in the garage, like Charles suggested. Wiring devices with UF is no fun.

+2 - a sub panel is the way to go. It will give you a lot more flexibility. And if your shop develops like most people's, you'll be making changes in the future.

Mike

[Tim Bridge]

A sub panel is a good idea, but I found that with my shop I only use one power tool at a time along with the dust collection. I could get away with one 20 amp 120 volt circuit for tools, one 30 amp 240 volt circuit for the bandsaw and one 20 amp 120 volt circuit for my shop vac. But that would be bare minimum. I have a few more circuits than that.

[Joshua Hill]

Well firstly, thanks to all of you for the input. I agree that a subpanel would've been the better route but for a host of reasons that I won't bore y'all with, I decided to go with the UF/Romex splices inside octo boxes. Thanks again for the sage advice gentlemen.

JLH