UF-B or pvc

[billconner]

I'm having some fill and top soil brought in to build up grade around new driveway and barn/garage Tuesday, and he's willing to toss in a trench for a drain and wiring to a new post light. I'll be at least 24" deep - just lawn - and was weighing the two alternatives. Leaning towards 1/2" PVC, partly because I have a bunch of thhn (from Chicago area house where conduit is required) with 2 elbows and stub ups, roughed in foundation to near road, about 80'. The conduit also allows a switched light and unswitched receptacle, not that I need it there.

What think thee?

 

[pima67]

If in conduit underground, you should use thwn not thhn because it is a wet location.

 

[billconner]

Got that. I need to see if it's dual rated.

If I use UF-B, is an elbow and piece of conduit to above grade usually acceptable?

 

[sparky 1971]

1/2 PVC is miserable to work with. The only thing it's good for is as a sleeve for UF to come from below grade.

 

[sparky 1971]

Got that. I need to see if it's dual rated.

If I use UF-B, is an elbow and piece of conduit to above grade usually acceptable?

Don't bother with the elbow if it's below grade.

 

[billconner]

1/2 PVC is miserable to work with. The only thing it's good for is as a sleeve for UF to come from below grade.

should I use 3/4"? 1"?

 

[sparky 1971]

should I use 3/4"? 1"?

Use 3/4" if your going to use THWN. If you use UF, a straight piece of 1/2" used for a sleeve will be fine.

You could also install a receptacle and switch the light using 12/3 UF, that will require using 3/4 for the sleeve.

 

[billconner]

I see the normal rule for UF-B in conduit from 24" below grade to 8' above. If under a deck or porch a few feet above grade, can it just be stapled to joists? Seems to be protected but not sure code thinks so.

 

[sparky 1971]

That's one of those rules that is subject to interpretation. I would call it protected under the deck if it were blocked off with lattice or something of the sort to keep people or animals from going underneath it. An inspector may or may not agree with me.

I don't sleeve it from 24" either. If the cable is turning straight up, I usually stick a piece of pipe over it to about 8" below grade.

 

[billconner]

Well, UF-B and some 1/2" pvc but in middle of night I remembered the need to call before you dig. I leave that to operator. I know it's clear to 10' from property line - it's the last 10'.

 

[mike93lx]

I hate UF-b, but think I would go that way for this. At 24", no one is accidentally hitting it with a shovel and an if it gets hit by a trencher or excavator down the road, pvc won't change anything.

 

[Norcal]

UF is a PITA to work with I always recommend PVC, but then again I flat do not like any kind of direct bury cable.

 

[billconner]

UF is a PITA to work with I always recommend PVC, but then again I flat do not like any kind of direct bury cable.

What makes it so hard to work with? Curling up? Need pins to hold it in trench? About to go purchase it.

 

[mike93lx]

What makes it so hard to work with? Curling up? Need pins to hold it in trench? About to go purchase it.

My experience is that it's a pain to strip, doesn't slide through conduit easily and isn't flexible.

 

[sparky 1971]

What makes it so hard to work with? Curling up? Need pins to hold it in trench? About to go purchase it.

Stripping the jacket without nicking the wires. It's not impossible with a little finesse. . It's a little harder for those of us that have little to no patience and want to use brute strength to accomplish all things.

 

[mike93lx]

Stripping the jacket without nicking the wires. It's not impossible with a little finesse. . It's a little harder for those of us that have little to no patience and want to use brute strength to accomplish all things.

Or have the wrong brand of linesmans

 

[sparky 1971]

Or have the wrong brand of linesmans

I'll have to take your word for it since I have no experience in that department.

 

[billconner]

A romex cable ripper doesn't do it?

 

[mike93lx]

A romex cable ripper doesn't do it?

The jacket is molded on instead of being a loose sheathing.

Ita not really a big deal, especially for a single circuit. The stuff is used all the time.

Maybe practice on some extra first

 

[mm08822]

Since you will have this in a trench you can allow for extra cable in case you have to re-do a botched stripping.

Ideal makes a nice UF stripper. I've used it on a few jobs that had a lot of UF. Works well. For only a couple of strips....not worth $60.

 

[sparky 1971]

A romex cable ripper doesn't do it?

Nope. I've found yhe best thing is a sharp sheepsfoot blade. I use the Klein cable splicers knife but have used the sheepsfoot blade of my pocket knife many times.

 

[wyliesdiesels]

A romex cable ripper doesn't do it?

nope. the jacketing is entirely different than nm-b. good luck

 

[billconner]

Surprised no one makes a clamp or similar that cuts through insulation.

Did find this UF cable ripper for $14:

Gorilla UF Stripper 10 in. Cable Stripper 46200 - The Home Depot

Quickly remove the outer jacket from wire cable in one pass by using this Cable Stripper from Gorilla UF Stripper. Won't nick copper wire.

www.homedepot.com

 

[CJ7VFR]

Surprised no one makes a clamp or similar that cuts through insulation.

Did find this UF cable ripper for $14:

Gorilla UF Stripper 10 in. Cable Stripper 46200 - The Home Depot

Quickly remove the outer jacket from wire cable in one pass by using this Cable Stripper from Gorilla UF Stripper. Won't nick copper wire.

www.homedepot.com

That cable ripper has really bad reviews. Be wary of buying this. A sharp sheepsfoot blade on a pocket knife does a really good job at stripping the insulation off of UF-B cable as Sparky 1971 said (and shown). The curve on the opposite side of the sharpened blade helps to keep the blade from gouging into the insulation around the individual wires of the UF-B versus using a regular knife blade which can puncture the insulation. My dad was in the Navy, and he used sheepsfoot blades all the time for cutting line and rope. When I was a kid he gave me a pocket knife exactly like the one Sparky 1971 has shown that I use all the time to strip UF-B.