I need to run a circuit to the tool shed. The trench is dug (2′ deep). I am planning to run 12/3 UF from the crawl space of the house out to the shed. In the crawl space I’ll install a j-box and then continue back to the panel with regular romex. My main question is about getting into the shed. Can I run the UF into a 3/4″ plastic conduit below grade (starting with an ell and then up thru a riser), into an LB, and then out the back of the LB into the wall with a j-box on the interior side of the wall? If not, what’s the correct way to get above grade on the exterior?
Edited 6/4/2005 1:20 pm ET by davidmeiland
Replies
Yes you can do that. You can also run it plain up the side of the buiding, but that is not as neet.
HOWEVER, most likely that area needs physical protection (from lawn mowers, weed eaters, hungry dogs) and sch 40 PVC is not rated for physical protection.
Sch 80 will do, but not available in the home horror and hardware stores.
Alternate ways are to use metal conduit (then you need to ground it) or to use something beside/around it to shield it. That coule be some thing like a ACQ 2x4 or metal post or steel pipe sleave.
Thank you Mr. H. I will sleeve the bottom section of the plastic riser with a piece of galv pipe. I've got just the thing taking up space in the barn.
Sch. 40 PVC is "resistant to impact and crushing", just not permitted when "subject to physical damage". I would think in most case, when run along a wall and secured to it, the inspector would have no problem with it. If it was freely accessible from all sides, though, the heavier stuff would probably be needed.
Consider what will happen to it if some bozo with a gas trimmer comes along. Anything you use should be able to withstand that.
I am personally the aforementioned bozo with the gas trimmer. I haven't tested it yet but it seems like I could eventually damage a piece of plastic conduit with the trimmer, so a bit of protection is in order.
A friend ran a lot of drip irrigation tubing. Problem was that her line trimmer was eating the poly tubing. I suggested using short lengths of 1/2" PVC conduit as a sleeve to protect the tubing. She installed the conduit and as of more than a year has had no problems with the trimmer damaging the tubing. SCH40 PVC conduit is pretty tough stuff. The plumbing pipe is more brittle. I can also say that most of the underground fed services are run in PVC and I can't say i have ever seen one that had been more than scratched by a line trimmer. Of course the services are run in 2" to 4" PVC so fewer edges to catch and I don't think if anyone installed a brush blade the conduit would last long.