depth to bury electrical conduit

[randy41]

the job is complete. the depth of the ditch is anywhere from 12-18". i put 2 1 1/4" grey pvc lines in one of which contains my 12/2 w ground UF cable. the other is awaiting the future need. i also put a 3/4" white pvc line in the ditch for water. not sure if i'm going to use it. i dug the 60' ditch by hand over several days. still backfilling (by hand) and i'll put a warning tape along the run above the pipes after they are covered by a few inches of dirt.
in my workshop building i ran the uf cable to a junction box and then hooked up to nmb cable to run to the breaker box.
sticker shock at the cost of 100' uf cable. it was just about half the cost.

 

[JerryK]

Some day you will pat yourself on the back for thinking ahead... when you run your T.V. cable out there, the internet cable, the phone line, the alarm system wires, etc..

 

[wrooster]

the job is complete. the depth of the ditch is anywhere from 12-18". i put 2 1 1/4" grey pvc lines in one of which contains my 12/2 w ground UF cable.

in my workshop building i ran the uf cable to a junction box and then hooked up to nmb cable to run to the breaker box.

sticker shock at the cost of 100' uf cable. it was just about half the cost.

1)
Per NEC and most local codes, minimum depth to the top of the conduit is 18".

2)
Running multi-conductor cable in conduit has to be approached with caution in several aspects, otherwise it is non-code compliant. Generally you pull individual THWN-rated wire through conduit, and only sleeve multi-conductor cable with conduit where necessary for physical protection.

3)
You can save a lot of money using individual THWN-rated wire compared to using UF cable.

Wrooster

 

[wrooster]

Put it in PVC it's water proof

You can use NASA-grade solvent glue for the joints and underground conduit will still fill with water. Ask any electrician if he has *ever* seen a bone dry underground conduit. The problem is condensation. The cooler-than-the-air surrounding soil causes condensation in the conduit, and it slowly fills with water. This is unavoidable.

For this reason, the NEC classes an underground raceway/conduit as a "wet" location, and the wire pulled through it has to be rated for use in a wet location -- e.g. THWN rated insulation (the "W" stands for "wet").

Wrooster

 

[grsthegreat]

1)
Per NEC and most local codes, minimum depth to the top of the conduit is 18".

2)
Running multi-conductor cable in conduit has to be approached with caution in several aspects, otherwise it is non-code compliant. Generally you pull individual THWN-rated wire through conduit, and only sleeve multi-conductor cable with conduit where necessary for physical protection.

3)
You can save a lot of money using individual THWN-rated wire compared to using UF cable.

Wrooster

agree 100%.. however since the job is done i probably wouldnt worry about it. it will last a long time, especially as its only a 20 amp service and is in conduit.
You could have saved alot of $$$ by using individual xhhw or thhn runs, but thats neither here not there as its completed.

good job using the future pipe. i did that and ended up using them to pull a 3 way for barn lights and internet/phone years later