1

I have a seasonal vacation home on patio blocks (no foundation) and a 14 x 20 shed on the property - located about 8' from the house. The panel in the home was on an exterior wall, until an addition was attached after I bought the home - now placing the panel 10' from the exterior wall - closest to the shed. This plus the ~8 of space between the house and shed puts the panel in the house a total of ~18' from the shed.

I'd like to feed a subpanel in the shed from the house. I was considering running a #6 UF cable between the two panels to support some outlets & lights in the shed and a 32A / 240V EV charger. After poking at the ground I found it would be very tough digging (even though only 8' from the house) and that the gravel bed under the shed would be difficult to control. I began to think about an aerial lateral instead, but am unsure about the best way to go about it. I have a little over 10' of height above grade on the house wall and 14' to the peak of the gable on the shed facing the house; so clearances aren't a concern. I would have to get power out of the panel from below and run power under the house in the crawlspace for about 10' to get to the house's outside wall - nearest the shed.

Any ideas?

Additional Discussion: My intention was to simply sleeve the UF cable between structures laterally for protection in Schedule 80 PVC. Since the cable is rated for direct burial; I didn't feel the need to use it as a complete raceway (space is very tight under the house). I would 90 up & through the sill to enter into the wall space of the shed. I'd then extend the UF to the panel - without additional pipe so no expansion fitting needed. Thankfully, there is a 200A service to the house and it would easily support the Nissan supplied 32A EV charger on a 2P40A breaker. The direct burial route of the UF cable is an issue not just for trenching; but more so when clearing a section of gravel for the vertical run of the pipe in the gravel bed that the shed sits on. Gravel will want to immediately backfill whatever is removed - eliminating the support "foundation' it provides to the shed wall and floor. This is my main reason for considering an overhead route. UF in PVC up the wall of the house and then attached to a messenger to support it between the buildings (while not aesthetically pleasing - but from what I'm reading - is permissible) and then sleeved in PVC again down the shed wall (or directly into the shed). This would eliminate the need for trenching and the problem of gravel backfilling disappear.

2
  • 1
    Welcome to Home Improvement, please take the tour. "Any ideas?" is a very broad, open ended question that invites opinions, both of which make it off topic. Consider an edit to your question to include a drawing of the site and of each of your two options and ask for Pros/Cons of them - that will give us some specifics we can comment on.
    – FreeMan
    Commented Apr 30 at 12:43
  • Are you asking if it is ok to run wire overhead? If so then say that you want to do that and ask what the codes are that you need to comply with.
    – RMDman
    Commented Apr 30 at 13:51

1 Answer 1

3

Consider RMC conduit. The stuff is usually dismissed out of hand because it's pretty expensive compared to PVC. However, when you're only going 8 feet, that's not actually a pain point.

The beauty of RMC is it only needs 6" of cover, so pretty easy to trench. You can switch to PVC at the expansion joint. Which you're using, right?

On the feeder, UF is usually a sucker bet because it has poor quality insulation and runs 10 amps lower than any other outdoor wire type. If you are direct panel to panel entirely in conduit, use THHN or XHHW, which is also much much cheaper (85 cents a foot per wire for #6).

Or if you'd really prefer to run 90A feeder, run #2 aluminum which is the cheapest option available. This will require larger conduit, though.

Now does your main service panel actually have the capacity to add 40A of EV charging? (and here, substitute the charge rate you'd actually prefer to have). If so, you'll want conduit simply so you can run a data line as part of an EVEMS system, with plenty of feeder capacity to the subpanel and the EVEMS operating in the main panel.

0

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.