direct bury wire from house to garage??? help

codeone · 01-19-2010, 10:42 PM

Yes ground rods ar required at a sub panel at a seperate building. And if you are under the 2008 NEC you also need an intersystem bonding bar/lug.

vinylman70 · 01-19-2010, 11:09 PM

Thanks for all the advise but i am getting lost when you all say save money and buy a smaller ground wire. And yes i know what you mean about lowe's when they say you need something when you know you dont. But if they have a 4 in 1 wire with 2 hot wire's and 1 neutral wire and 1 ground wire all number 2 copper wire all in one for 292 bucks how does a man save money buying 4 seperate wires 3 number 2 and say 1 number 4 for a ground when the price per foot is .80 you x's that by 4 thats about $515 my father in law has a bunch of pvc pipe out back by the woods he said i can have so i guess if i use the direct bury i will also put it in that will that work. I dont plan on ever running more wire to the garage as this will be all i need as long as it runs a welder and lights at the same time i am happy i dont plan on running a welder,lights,grinder,and a huge air compressor all at the same time so this should work right? Thanks everone you all are a big help i cant tell you how much you all have helped me.thanks let me know

Scuba_Dave · 01-19-2010, 11:32 PM

Many people have "saved" money by burying wire
Many people never have a problem
Many have also cursed it when they have to dig it up & buy & bury new wire due to some problem with the direct burial wire

Once you bury conduit you can easily replace the wire if there is ever a problem
You need to use electrical conduit - grey....not white

vinylman70 · 01-20-2010, 12:06 AM

ok. i have also been in the search bar and what i have also read and like what you have said is for people to use 3 number 2 wires and a green number 10 wire for a ground. with 2 8'x1/2'' ground steaks at the garage right. if i do that what size pipe do i need to use. 1 1/2 all 4 wires go in the pipe right? also just wondering why do i read that people have trouble with the direct bury just wondering what kind of problems are with it. also if i do stick with the direct bury can i run it in the pipe so it can be replaced if ever needed?? reason im full of questions is because im on a budget and i have had my garage since march of 06 and really want some electricity out there while i do have some money.i had the trench dug in 07 and filled it in this year and now have some money so i already have to do this work again.

Scuba_Dave · 01-20-2010, 12:12 AM

You would use (3) #2 wires & I think #4 ground - 2nd size down
2 ground rods with #6 wire Min running to them
I'd run 2" pipe....1.5" would meet code

You could run the direct burial in the conduit
But you would need much bigger conduit due to the fact it is a cable

Problems with direct burial:
Critter chews on underground
Lightning strikes
Rock pokes thru the cable
not sure what else...and again it may never happen

I ran (2) 20a buried circuits out front & still used conduit

vinylman70 · 01-20-2010, 12:44 AM

ok dave all makes since tomorrow i will check on the price of 3 #2 wires and a #4 wire all 160feet and i guess price on 160 feet of the pipe and see what it will cost that way then add the price of pipe to the direct bury and see what it will cost that way to. with the direct bury in the pipe should add security to it though right and be just about the same?? do you know about what the pipe runs? on just wire i will need 2 black for hot 1 white for neutral and what color for ground? or am i wrong? or is it all the same

kbsparky · 01-20-2010, 02:08 AM

WE'd use (2) #3 hots, (1) #4 neutral, and (1) #8 ground. All installed in a 1¼" conduit. Fully rated for 100 Amps. #2 wires are overkill.

vinylman70 · 01-20-2010, 02:40 AM

can some one tell me a web site that shows this wire because when i google it all it wants to show is either electric fence wire and wire for amp's aint having no luck lowes web site dont even show it but i did find the conduit it was je eagle 2''x10' for $2.98

vsheetz · 01-20-2010, 03:53 AM

Quote:

Originally Posted by vinylman70

Thanks for all the advise but i am getting lost when you all say save money and buy a smaller ground wire. And yes i know what you mean about lowe's when they say you need something when you know you dont. But if they have a 4 in 1 wire with 2 hot wire's and 1 neutral wire and 1 ground wire all number 2 copper wire all in one for 292 bucks how does a man save money buying 4 seperate wires 3 number 2 and say 1 number 4 for a ground when the price per foot is .80 you x's that by 4 thats about $515 my father in law has a bunch of pvc pipe out back by the woods he said i can have so i guess if i use the direct bury i will also put it in that will that work. I dont plan on ever running more wire to the garage as this will be all i need as long as it runs a welder and lights at the same time i am happy i dont plan on running a welder,lights,grinder,and a huge air compressor all at the same time so this should work right? Thanks everone you all are a big help i cant tell you how much you all have helped me.thanks let me know

PVC pipe for water usage, and electric conduit are differing. Per code, proper electic conduit is required.

vinylman70 · 01-20-2010, 04:37 AM

just so you all know there are no codes involved here it will never be checked. where i live at it is basically do what you want to do. it's more less a red neck town. you go a county away it's like beeing in a city and you must follow code there is a big diff. between my county and the rest of tennessee. if anything were to ever go wrong it would just throw the breaker at the house i mean im confussed i have never done this my dad is a electrician he wired the garage and was suposse to do this to but he more less bailed and moved away so now it is up to me he said i need number 1 wire that will draw at least 150 amp then i have been told number 2 wire and in a more recent post it has been said use 2 #3 and a #4 and #8 and dad also said the direct bury from lowes would work as long as i dont try running everything at once at the most welder and lights. all i know is we are allowed to do this 1 time where i live to join on to the extension box off the house and run electric to a garage or what ever it be but we cant do it time and time again. or do it as a living unless you are licensed to. anyways thanks for all the help i just need to know the right wire to use so i dont waist my money. im not saying i wont buy the #2 wire but if i can save money and buy a cheaper wire that will work please let me know. if the guy that said #3,4,8 will work what does everone else think. thanks right now im pretty well thinking #2 and #4 or direct bury in conduit this is a great board and i appreciate every ones help greatly please dont take this reply wrong im just saying what i have been told and what little i know i already have $600 invested is just the wiring in the garage yes it was to dad 3 years ago but i still love the man even though i got the raw end of this

kbsparky · 01-20-2010, 06:32 AM

The wire we use for this is type THHN-THWN-2. Most places call it THHN, although it is dual rated. This is copper conductors, and it is required to install it in conduit.

The direct-bury stuff would be commonly called #2 URD. This is an assembly of 4 aluminum conductors twisted together, with the neutral and/or grounding conductors reduced in size. I've seen it configured as either 2-2-2-4, or 2-2-4-6.

While a 3-conductor version of #2 URD may be available, you need 4 conductors for this project.

Places like Lowe's and the Home Depot sell it as 100 Amp mobile home feeder.

You can use a 100 Amp breaker, and directly plug it into the blank spaces in your main disconnect box.

If you use the direct-bury URD cable, you still will need a short section of PVC conduit to sleeve the wire where it emerges from the ground, for physical protection.

Does that help?

vinylman70 · 01-20-2010, 03:50 PM

thanks kbsparky i understand thanks for all the help.

vinylman70 · 01-20-2010, 08:59 PM

ok i went and seen our main man of our town that calls all the shots he also owns his own hardware store and has been building some nice 150,000+ new homes down the main highway. he said we needed to do direct bury and he has never had any problems with it for 17+ years he said we would use #3 aluminum wire. he said there was no since in having a 4th wire for ground at all and said it would pull every bit of 100 amps all this at $1.20 a foot so it looks like this will be less expensive than i thought. and said they would also do it for me for $200 thats digging a new trench and hooking it all up

he also asked if i wanted codes to inspect i said na he said thats fine........................

Scuba_Dave · 01-20-2010, 09:18 PM

A 4th wire is required for safety & to meet current code
#3 Alum is good for 75a max

vinylman70 · 01-20-2010, 10:39 PM

i see what your saying scuba dave i guess there must be big diff. between our regions. anyways the welder shows it has the amp range of 25-185 and is 230 volt so do you think the 75 volts that you say i will only get run that welder and lights at the same time remember i will not be running welder,lights,and a 230v air compressor and small tools at one time at the most just welder and lights when i asked him about the #2 direct bury wire he said no one ever uses it because it is expensive and that every body just about uses this direct bury aluminum wire and it is very popular and said it would pull 100 amp unless we hit the 200 foot mark and it would be all i need. he said just about every one was useing this same wire around here??????????let me know.