[Florida] Electric to shed 160ft from main breaker, Q's to help me talk to my electrician

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guy1337

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Home owner, non-DIY
Hello fellas, just want to say up front that this isn't going to be DIY. I have some questions in regards to best practices for my situation so that I may better communicate with the licensed electrician i'm hiring.

East coast Florida, new shed on property ~160ft from main panel box that is mounted outdoors on a pole. Want to provide power to the shed to handle a TV, 2 computers w/ monitors, window unit 120v AirCon, lights, stereo etc. Electrician mentioned over phone about possibly running a single direct bury cable from main panel to the shed and installing another panel in shed. I asked if I could do the trench and he said yes, 12".

I did some searching and seen a couple different things about depth of cable and whether or not to conduit. I'm curious if 12" direct bury is the best way to go for a task like this? I assume depth is important for a reason, such as cable shifting/erosion or something else I may be unaware of?

I ran some searches online and on the forums but most people with a shed situation seem to only be wanting enough electricity for lights. I assume those situations are differnt from mine due to the amount of items I want to power, no?
 
Have the electrician do a load calc and voltage drop.
Ask him about burial depths in 300.5
I would not do direct burial, install 2 conduits.
A permit is probably required.
 
Thanks for the advice fellas. Definitely not DIY-ing the job myself -- when it comes to electricity, there are things that I don't know that I don't even know about. Feeling more confident discussing it with him, cheers again.
 
guy1337 said:
I'm curious if 12" direct bury is the best way to go for a task like this? I assume depth is important for a reason, such as cable shifting/erosion or something else I may be unaware of?
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As Tom said, conduit is much better than direct bury. The reason for two conduits is because digging is hard and expensive, whereas PVC conduit is easy and (relatively) cheap. Keep the second conduit as a spare in case you want to add capacity to the shed in the future.

The depth is important for protection against damage from above, like someone digging up weeds over the conduit/cable. I'm concerned about your electrician because the depth he stated is insufficient for the job. Also, the depths listed in 300.5 are Minimum Cover Requirements which means that the trench must be dug deeper than the stated dimension.
 
tesi1 said:
IF YOU HAVE COMPUTERS AND A TV YOU WOULD NEED A CONDUIT FOR COMMUNICATIONS
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NOT NECESSARILY. (don’t yell) with all the wireless around now.
I assumed the recommended second conduit was for communication. I would have a tendency to space the two at least a foot apart. Depth would be a minimum of 18” to top of raceway

Some of the POCOs here require at least two raceways buried for commercial projects but never for residential.
 
Years ago I made a list of things that would need a trench from my house to my barn/shed. Digging the trench is probably the most difficult part of the job. As long as you have the trench open, you might as well include:

Power - lights, heat, A/C, etc.

Power 2 - In case I installed a generator in the barn and wanted to feed power TO the house.

Communications - phone, cable TV, intercom, Internet, etc.

Water - have to keep this one away from the power!

I don't have my full list handy, but there were about a dozen things that you might want at the shed and don't want to walk back to the house for!

Best to think about everything you can do in the house, and how you would do that in the shed.
 
Those of you commenting on the 'terrors' of trenching might note that the OP is on the east coast of Florida. I once dug, with a spade, ~100' trench 18" deep in that beautiful Florida sand. Barely broke a sweat!
 
I was with a group of Scouts on an island in the Delaware River. We were building a hut and needed to dig post holes for the saplings to stand in. We started digging... and digging... and digging... I think we were 3 or 4 feet down before we realized we were deep enough! It was all sand!

Of course, when we wanted to re-insert a tent peg we couldn't find a rock to use as a hammer! Had to use the heel of someone's boot!
 
g3guy said:
Those of you commenting on the 'terrors' of trenching might note that the OP is on the east coast of Florida. I once dug, with a spade, ~100' trench 18" deep in that beautiful Florida sand. Barely broke a sweat!
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You can come and dig all my Florida trenches. I hate trenching. I usually run rigid conduit so I don't have to dig deeper that 6" to top of pipe rather than 18". Tried using a Ditch Witch for a job recently to dig a 22" deep trench for PVC. Spent more time repairing sprinkler and well pump lines (water and power) than I would have if I had hand dug. BTW, yes we have sand but there are an awful lot of big roots as well.
 
Coppersmith said:
Tried using a Ditch Witch for a job recently to dig a 22" deep trench for PVC. Spent more time repairing sprinkler and well pump lines (water and power) than I would have if I had hand dug. BTW, yes we have sand but there are an awful lot of big roots as well.
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This is why I always backfill trenches with sand to cover conduit and piping and lay marking tape on top. And draw up a good "as built" plan. You never know when someone else will have to dig there in the future.
 
There’s plenty of sand here in Florida and plenty of roots. I often spend as much time with the sawzall In my hand as I do the shovel when digging trenches.
 
PaulMmn said:
Years ago I made a list of things that would need a trench from my house to my barn/shed. Digging the trench is probably the most difficult part of the job. As long as you have the trench open, you might as well include:

Power - lights, heat, A/C, etc.

Power 2 - In case I installed a generator in the barn and wanted to feed power TO the house..........
Click to expand...

I put a generator input in my shed, upsized the conduit and ran the backfeed cable in the same conduit as the feeder to my house’s main panel to a 60 amp generator breaker and an interlock. I used 2-2-2-4 mhf for the 90amp shed subpanel feeder and the generator backfeed cable. Failed inspection. Ahj said cable fill was fine, generator cable was fine, but with six current carrying conductors I had to derate ampacity for the feeder . I said there would only be six ccc if the genset was running which means the current in the feeder would be limited to 60 amp max from the generator breaker. He wasn’t convinced. For the cost of a few sticks of conduit it wasn’t worth arguing so I have one for power and one for the generator backfeed.
 
Wow, tons of great info and insights for me to think of in regards to planning any future runs to the shed that I may have not thought of. Will most likely be going with a conduit pipe or two as well. Will bring the conduit info up and give him a list of what all I may be wanting the shed to power.

In regards to the trench, yup i'm lucky due to location in Florida and the yard isn't covered in trees. The only problem was about 10ft of crushed shell rock parking spot that had been compacted over the past 17 years. A 5lb fiberglass mattock chipped it away in no time though. Disassembled a clamshell post hole digger to use as a skinny shovel for scooping.

Thanks again fellas, considering my question fully solved!
 
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