electrical detached garage ?

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Any electricians in the group? Building a detacted garage about 12 feet from the house. Want to put in a 70amp subpanel. From what I've read the garage need's to have it's own grounding rod. And I need to run both hots, a neutral, and a ground from the main panel. And the ground and neutral need to NOT be connected together in the sub panel.
Have I got this right???
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*You are correct. You need four conductors to the subpanel and the ground and neutral are kept separate whereas in the main panel they are bonded together. The grounding electrode conductor from the ground rod at the garage gets connected to the ground bar in the subpanel. You may have to buy the ground bar separately from the circuit breaker panel.
Do a search in alt.home.repair. This topic has been answered many times in that group.
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snipped-for-privacy@gmail.com wrote:

You got it. But you don't need 70A in a detached garage. 30 would be more than ample. (no pun intended)
steve
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wrote:

Thanks :-)
Sorry my bad, detached 28x30 garage with finished space above. I need to run a 1 1/2 ton heat pump (too big but the smallest they make in a conventional split) and a 20 gallon hot water heater. Plus the usual lights/outlets. Garage will be a bit of a workshop as well. Got a 6 space panel. 2 for the heat pump, 2 for the hot water. One 20amp for outlets in the garage on 12/2. One 15 amp for lights and outlets in the space above on 14/2. Was figuring on putting one upstairs outlet on the 20amp circuit for a microwave. Will be a "bar" style kitchenette at one end, little fridge and microwave. Also a 3/4 bath in a dormer.
I did see that the question had been answered a lot but like everything else on the internet there were a lot of different answers :-) Wanted to make sure I had picked the best answer.
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wrote:

*I would put in a 20 space panel to allow for future expansion. A kitchen requires two 20 amp circuits and a bathroom one 20 amp circuit. Check out these small package units from Friedrich. They are great for apartments and condos and you don't need a technician to install them: http://www.friedrich.com/products/LineOverview.php?line=A
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It's not really a kitchen, more like a bar. And I figured I could get away with just using running the 3/4 bath off the 15 amp that the lights and outlets are on. Think that's a bad idea? The living space is inside a 12 in 12 a frame roof with a 14' shed dormer on the back and a couple conventional dormers on the front so it's not really all that big.
http://home.earthlink.net/~jamesgangnc/garage /
Yea but all the alternative hvac systems all seem to cost 2 or 3 times as much as conventional splits. Guess that's do to volume. Cost is a factor of course. And I can do a split install, just have to use silver solder on the freon lines since my copper brazing skills suck :-)
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wrote:

It's not really a kitchen, more like a bar. And I figured I could get away with just using running the 3/4 bath off the 15 amp that the lights and outlets are on. Think that's a bad idea? The living space is inside a 12 in 12 a frame roof with a 14' shed dormer on the back and a couple conventional dormers on the front so it's not really all that big.
http://home.earthlink.net/~jamesgangnc/garage /
Yea but all the alternative hvac systems all seem to cost 2 or 3 times as much as conventional splits. Guess that's do to volume. Cost is a factor of course. And I can do a split install, just have to use silver solder on the freon lines since my copper brazing skills suck :-)
*Code requires 20 amps for the bathroom unless there is only a toilet with no sink or shower. If someone uses a blow dryer in there you will regret sharing it with another 15 amp circuit. It's up to the inspector to determine if the bar can be considered a kitchen or not, but if it was me I would put the two 20 amp circuits in there. The usage of the space may change in the future and you may add more appliances. I prefer to keep the lighting circuits separate from the outlet circuits when wiring rooms from scratch.
Don't short change now while it is being built and the easiest time to install wiring (And plumbing). If you haven't already planned to do so you should consider prewiring for telephone, TV and computer.
I got a great deal on one of those Friedrich units several years ago from Johnstone Supply because I am an electrical contractor.
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Yea. your'e probably right. I should switch to an 10 space panel rather than regret it. It's not like they are expensive or anything. I will run r6, phone, and cat5 while I'm at it.
Any thoughts on running power, water, and sewer through a 15" by 9" chase? I have no idea how code treats an exterior chase between buildings.
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wrote:

Yea. your'e probably right. I should switch to an 10 space panel rather than regret it. It's not like they are expensive or anything. I will run r6, phone, and cat5 while I'm at it.
Any thoughts on running power, water, and sewer through a 15" by 9" chase? I have no idea how code treats an exterior chase between buildings.
*Off hand I don't see a problem with the utilities combined in one chase. However you should check with your building department as they are the ones who can say yay or nay. Put in a 12/20 panel. 12 spaces, 20 circuits or a 12/ 24. You want more room for expansion.
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I think the key work here is 'external'. As long as you treat everything inside the chase is if it was truely external (exposed) you shouldn't have any problems. Remember to keep the AC and the low power the required distance apart (I forget the exact space but it's like 12" or so) so there won't be any issues with induced power and/or interference. It wouldn't hurt to put some of that nice closed foam snap-around insulation around the water and sewer pipes as well.
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Just curious. How are you getting power to the garage, aerial or underground? You got all the details figured on that too?
--
Dave

CDOs are how we got here.
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On Feb 23, 11:08am, "Dioclese" <NONE> wrote:

That might be a bit sketchy code wise :-) The garage sits about 12 feet away from the house. There is wrap around a deck that will hit the garage about midway between the garage floor and the floor above. The house ground floor is at the deck level. The house has a crawl under it with about 5 to 6 feet of headroom. I'm going to put a landing on the inside stairway of the garage for an exterior door on to the deck. My thought is to build a chase under the deck and run all my utilites, power include through the chase. The deck joists are 2x10's on 16" so the space for a chase would be between two of those deck joists. Looks like I can get enough drop for the sewer return in that space. Thought is that if I have the chase open to the crawl space, between that and the heat from the sewer pipe it will keep a water supply line from freezing. House is at the NC/VA line. I don't plan to have any water except exterior hose bibs on the garage floor so it will be ok to have the sewer enter the garage midway. Sketchy part code wise is running all that stuff through a chase, not sure if that is cool or not.
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That might be a bit sketchy code wise :-) The garage sits about 12 feet away from the house. There is wrap around a deck that will hit the garage about midway between the garage floor and the floor above. The house ground floor is at the deck level. The house has a crawl under it with about 5 to 6 feet of headroom. I'm going to put a landing on the inside stairway of the garage for an exterior door on to the deck. My thought is to build a chase under the deck and run all my utilites, power include through the chase. The deck joists are 2x10's on 16" so the space for a chase would be between two of those deck joists. Looks like I can get enough drop for the sewer return in that space. Thought is that if I have the chase open to the crawl space, between that and the heat from the sewer pipe it will keep a water supply line from freezing. House is at the NC/VA line. I don't plan to have any water except exterior hose bibs on the garage floor so it will be ok to have the sewer enter the garage midway. Sketchy part code wise is running all that stuff through a chase, not sure if that is cool or not.
---------- How far you are from the Atlantic Ocean coast determines mostly the degree from freezing you'll need. East, on the coast, isn't so bad. When you get near the Apps, it becomes more critical.
I'd put the cable in armored flex-conduit above ground. Another option is burial. Check out the power entrance requirements needed for the garage in whatever method you choose.
--
Dave

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On Feb 24, 1:12pm, "Dioclese" <NONE> wrote:

.
It's on kerr lake so not close to the coast but not any great elevation either. Septic tank right outside the house with a pump up drain field so I expect there is some warmth in the drain pipes. No vent on the tank. I was thinking maybe wrap the supply line with a 3" drain line together. Plumbing is cpvc so I would expect it to tolerate some light freezing.
I'm not sure why I'd put the cable inside conduit when it's already protected? Does that lower the current rating unless I use individual wires? I was thinking about using aluminum 4/3 with a ground. It's a lot cheaper than copper.
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It's on kerr lake so not close to the coast but not any great elevation either. Septic tank right outside the house with a pump up drain field so I expect there is some warmth in the drain pipes. No vent on the tank. I was thinking maybe wrap the supply line with a 3" drain line together. Plumbing is cpvc so I would expect it to tolerate some light freezing.
I'm not sure why I'd put the cable inside conduit when it's already protected? Does that lower the current rating unless I use individual wires? I was thinking about using aluminum 4/3 with a ground. It's a lot cheaper than copper.
*The cable and individual conductors would need to be rated for wet locations. It sounds as though you are planning to use service entrance cable. It would be cheaper for materials to install PVC conduit and pull four wires.
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I'll take a look at that option. I have to go into the crawl under the main house from an outside box, down a wall about 25ft, and then across under the deck to the garage. My plan is to put the subpanel fairly close to where the line comes in. The service entrance wire looked like the cheapest but I did not look at the price on individual aluminum #4. I know the conduit wouldn't be much.
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What does your code say about the additional ground rod?
Could cause problems with two separate grounds.

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Bill wrote:

you cannot have too many grounds. BUT, having said that, he still needs the separate ground all the way back to the main panel if he has ANY other metallic connections between the buildings.
steve
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wrote:

Since phone and tv count looks like I do.
I returned my 6 space box and picked up a 12 space one. So I'll have 2 for hot water, 2 for the hvac, one 20 for the garage outlets, one 20 for the garage 3/4 bath, one 20 for the bar area, one 15 for all the lights and one 15 for the upstairs outlets. And 3 spares.
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snipped-for-privacy@gmail.com wrote:

Sounds like a deal. 'cept i'd run a 20 to those upstairs outlets. I don't use any 14 ga wire at all any more except for some limited lighting circuits. How many outlets upstairs and what's going to be plugged into them?
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