12/2 Romex in 1/2 inch PVC conduit?

[Andy_GTS]

I'm placing a 20 amp gfci outlet on the exterior of my house. The optimal location for the wire to exit the house is ten feet away from the outlet location. I was planning to use 1/2 inch sch 40pvc conduit. It will be under a deck approximately 8 inches above grade. Is this considered a wet location? Can I use 12/2 romex or do I need to pull thhn for that 10ft run?

I searched but found conflicting information on what is considered a wet location. Also found conflicting information on romex inside conduit.

Thanks GJ!

 

[pattenp]

Any conduit installed outside is considered a wet location and NM (Romex) is not approved for wet locations. NM can be placed in conduit but the fill limits are calculated using the widest dimension of the cable for the area and the NM is considered one as one conductor.

 

[Andy_GTS]

Any conduit installed outside is considered a wet location and NM (Romex) is not approved for wet locations. NM can be placed in conduit but the fill limits are calculated using the widest dimension of the cable for the area and the NM is considered one as one conductor.

So for my project I need to pull THHN?

 

[pattenp]

You can use 12-2 UF. Also use a WR rated outlet in a weather proof box.

 

[Bert_]

You can use 12-2 UF. Also use a WR rated outlet in a weather proof box.

What he said. If you don't want to run conduit for the whole run (inside portion) then UF is the way to go.

If you do run conduit from one box all the way to the other then THHN is easier to pull.

 

[Andy_GTS]

What he said. If you don't want to run conduit for the whole run (inside portion) then UF is the way to go.

If you do run conduit from one box all the way to the other then THHN is easier to pull.

Can I run NM to a junction box and then either thhn or uf? Or do I need to do all one type for the run? I'm not running the conduit to the panel, only the exterior 10ft of the run.

 

[pattenp]

Can I run NM to a junction box and then either thhn or uf?

Yes. But you may find it easier to use UF for the complete run and not bother with the junction box for doing a splice. It's your choice. I'd probably go with 3/4" PVC conduit if using UF.

 

[klassenl]

Just use the 12/2 in the conduit. It will work well and you will have no problems.

 

[PoorOwner]

Can I run NM to a junction box and then either thhn or uf? Or do I need to do all one type for the run? I'm not running the conduit to the panel, only the exterior 10ft of the run.

Yes you can, anything once you exit the stucco/siding surface of the house is considered wet location. Just nut it to the 12 THWN and done, the conduit is so short you don't even need to fish it, just push it inside. Save what's left for other garage surface mount electricity projects.

 

[CJ7VFR]

I have a question. Say you wanted to mount a water proof box on the outside of your house, and the wiring was going to go right into the box from the inside of the house, thru a hole in the house, directly into the box, with no conduit runs or anything, do you have to use "wet location" wires for this?

Or can you run NM wire from the inside of the house, thru the hole, and directly into the outside box?

Jim

 

[dnwong]

What he said. If you don't want to run conduit for the whole run (inside portion) then UF is the way to go.

If you do run conduit from one box all the way to the other then THHN is easier to pull.

So, can one use schedule 40 pvc as a sleeve on a portion of the UF cable that is exposed outdoors? What type of box or transition would you use going into the wall?

 

[Falcon67]

Any conduit installed outside is considered a wet location and NM (Romex) is not approved for wet locations.

Oh well. The pool pump feed has been there 4 years now - runs 12' long the wall and around the corner of the house. Works well, no issues. It's copper wire wrapped in plastic, stuck in a plastic tube.

I used outdoor rated boxes, drilled a hole in the back of one and mounted it over the box that had a non-GFCI plug (on the back porch - changed that to a GFCI of course) and pulled the wire through to the new box. Caulk, used a weather plug cover for the GFCI then ran the conduit from that box to were I needed a plug for the pool pump.

I have a question. Say you wanted to mount a water proof box on the outside of your house, and the wiring was going to go right into the box from the inside of the house, thru a hole in the house, directly into the box, with no conduit runs or anything, do you have to use "wet location" wires for this?

Jim

Never seen it done. Just regular "romex" in the outdoor boxes. This house was built in 2001 and not a single exterior outlet had a water proof cover. Or GFCI. And yes, it - apparently - was inspected.