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K8096

Garage wiring estimate

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If you're thinking of ceiling radiant heat panels, they will do a great job since they warm the objects in the room, not the air. Grainger's sells a 2 x 4-foot radiant panel that consumes 750-watts. You could put two on a 20-amp circuit. You'd probably need 10 of them.

Had I had it to do over again I'd run PEX tubing in the concrete and heat the floor. It's cheap and efficient. All you need is a hot water source, thermostat, zone valve and tiny pump.

The rest of my house is heated hydronically and I love it.

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I have a Dayton g73 heater from Grainger in my garage, 24x24 with 12ft ceilings in southern PA and it will make it like Jamaica in there if you want it. My garage is insulated all around including the door. The current draw of the heater should be listed in the specs.

Someone else commented on weather you can run a 200A sub from a 100A panel. No you cannot. Your subpanel cannot be rated higher than your main panel. However I still recommend 200A service to a garage/shop. If it is strictly a garage to park cars in you will have no issues with 100A but I always seem to have too few outlets and 2 phase power in every garage I have ever had.

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If you're thinking of ceiling radiant heat panels, they will do a great job since they warm the objects in the room, not the air. Grainger's sells a 2 x 4-foot radiant panel that consumes 750-watts. You could put two on a 20-amp circuit. You'd probably need 10 of them.

Had I had it to do over again I'd run PEX tubing in the concrete and heat the floor. It's cheap and efficient. All you need is a hot water source, thermostat, zone valve and tiny pump.

The rest of my house is heated hydronically and I love it.

I agree 100% I had radiant floor heat in my last shop in NH and it was great, nice and warm and the floor was comfortable to lay on. It did take a while to heat up however so you have to maintain a certain temp all the time but it didn't seem to cost an arm and a leg to do that. I ran mine off an oil fired furnace that heated the rest of the house as well. Radiant heat is also the most comfortable I think, you don't get the "breeze" as with the electric heater I have and the temp is more stable. I just wanted cheap easy heat in my new garage so I went with the G73.

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I did 2 inch thick high density foam insullation sheets under my conctere floor and I do have the fully insulated garage doors too. Eventually I'll insulate the whole garage as well, including the ceiling (after wiring done) and I'll use the 5/8 inch thick fireproof drywall. I work full time and have 2 little kids so it will take a few years to finish.

My house was updated to 200 amps a couple years ago, so I'm definately running a wire from the house to the attached garage.

I looked up the Dayton G73 heater. It takes a dedicated 220 line and needs a 30 amp curcuit. Looks like actual amp draw is 21 amps. It heats up to 500 sq feet, so if I got one of those, I would for sure have to "curtain" off 1/2 the 25 X 50 garage. Cost is about $400 plus $18 for a ceiling mount kit. Not bad. I'd probably just have to make sure I didn't run the large compressor at the same time as the heater.

A friend of mine worked at a Ford dealer and they had just got in a brand new ceiling mounted commercial grade electric heater. The dealership went out of business before it could be installed so he got it for a song and installed it in his 1500 sq ft garage and loved it. This was back in the early 1980's.

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You should be able to rent a trencher, much like you use to install a new sprinkler system.

acquire the necessary wiring, and the correct conduit (your local building department maybe able to assist you in which type to use. If your electrician is will to work with you, you install the boxes, and pull the wiring in the garage, and he does the connections. Thats what I did and I was able to cut the cost down by about a third.

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In Australia and New Zealand where the power is all 240 volt, all electrical work must be carried out by a registered electrician. It is illegal to do it yourself. 240V kills.

If the power supply to your shed is going to be underground you could install the conduit yourself with a draw wire through it so the electrician can pull the cable through and that would lower the price quite a bit. Feed the draw wire into each length of conduit as you are installing it.

David

I too, am an electrician and that's not a bad price. However, the main feed between house and garage is pretty basic DIY stuff. You should be able to get a "Homeowner's permit" which will allow you to do the bull work yourself.

If you don't plan on future trenching in the area of the cable use direct burial conductors.

Just so you know, the system in the garage will be considered a sub-panel and will require a separate neutral and ground, so you'd be burying 4 wires.

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I would gather from the original post date of this thread the project may be well beyond the planning stages and perhaps even the construction stage but for persons who might be also entertaining a similar project a few planning hints that may save a lot of money and perhaps frustration in the long run.

Before planning any such project it will be wise to check local requirements for necessary permits, even if you live in an unincorporated area outside of an incorporated area, but within 1 to 5 miles. Extra territorial jurisdictions may extend their permitting authority to your location depending upon the state where one is located.

Secondly, check with your insurance agent. Your new building will not necessarily be covered by present home owners insurance. Additionally, provisions of the policy could be voided if any alterations have been done without appropriate permits or electrical work not having been done in accordance applicable local codes and/or the National Electric Code.

Third, previous comments on help from the counter guy at a distributor or retail store should be taken with a grain of salt. There is every likelihood that person is not and expert on building codes in your particular area and it is very unlikely they are licensed in any trade, otherwise they wouldn't be doing what they are doing. Probably knowledgeable about the quality of different products they sell, but not necessarily competent on application.

Things to think about!

Climate always plays a roll to the extent of any anticipated heating and A/C desires or requirements in the long run. Then there is the issue of what shop equipment will or maybe added in the future, i.e.; compressor, TIG or MIG welder, lift(s). A typical shop for hobby restoration work will need at least three maybe four 230/240 dedicated runs in place initially to be on the safe side even if the equipment isn't to be purchased and installed immediately. There is never such a thing as too many 110/120 wall outlets particularly along walls where work benches may be placed and in my mind no more than two to four outlets in a shop should be placed on the same breaker to avoid those unwanted breaker trips. The amp draw of many bench mounted tools will often be greater than you might think. Two electrical devices simultaneously on and each drawing more than 10 amps will indeed trip a 20 amp breaker!

Ceiling light circuits should not be placed on the same breaker with wall outlets in my mind unless one doesn't mind looking for a flashlight in the dark because you can't see the breaker box after a breaker trips. (you will eventually by accident overload circuits and trip breakers if a short in some device doesn't do it for you). Wire of the correct gauge for a run and boxes are cheap in comparison to having to correct oversights in the future; and beside who wants to find out the hard way they should have spent a few more bucks in the beginning to be able to use that suddenly desired or needed electrical tool.

Most of all don't let doing something for less override common sense and good practice. The "5 P" theory of "Proper Planning Prevents Poor Performance" should always be foremost in the mind.

Just sayin'

Jim

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I would gather from the original post date of this thread the project may be well beyond the planning stages and perhaps even the construction stage but for persons who might be also entertaining a similar project a few planning hints that may save a lot of money and perhaps frustration in the long run.

Before planning any such project it will be wise to check local requirements for necessary permits, even if you live in an unincorporated area outside of an incorporated area, but within 1 to 5 miles. Extra territorial jurisdictions may extend their permitting authority to your location depending upon the state where one is located.

Secondly, check with your insurance agent. Your new building will not necessarily be covered by present home owners insurance. Additionally, provisions of the policy could be voided if any alterations have been done without appropriate permits or electrical work not having been done in accordance applicable local codes and/or the National Electric Code.

Third, previous comments on help from the counter guy at a distributor or retail store should be taken with a grain of salt. There is every likelihood that person is not and expert on building codes in your particular area and it is very unlikely they are licensed in any trade, otherwise they wouldn't be doing what they are doing. Probably knowledgeable about the quality of different products they sell, but not necessarily competent on application.

Things to think about!

Climate always plays a roll to the extent of any anticipated heating and A/C desires or requirements in the long run. Then there is the issue of what shop equipment will or maybe added in the future, i.e.; compressor, TIG or MIG welder, lift(s). A typical shop for hobby restoration work will need at least three maybe four 230/240 dedicated runs in place initially to be on the safe side even if the equipment isn't to be purchased and installed immediately. There is never such a thing as too many 110/120 wall outlets particularly along walls where work benches may be placed and in my mind no more than two to four outlets in a shop should be placed on the same breaker to avoid those unwanted breaker trips. The amp draw of many bench mounted tools will often be greater than you might think. Two electrical devices simultaneously on and each drawing more than 10 amps will indeed trip a 20 amp breaker!

Ceiling light circuits should not be placed on the same breaker with wall outlets in my mind unless one doesn't mind looking for a flashlight in the dark because you can't see the breaker box after a breaker trips. (you will eventually by accident overload circuits and trip breakers if a short in some device doesn't do it for you). Wire of the correct gauge for a run and boxes are cheap in comparison to having to correct oversights in the future; and beside who wants to find out the hard way they should have spent a few more bucks in the beginning to be able to use that suddenly desired or needed electrical tool.

Most of all don't let doing something for less override common sense and good practice. The "5 P" theory of "Proper Planning Prevents Poor Performance" should always be foremost in the mind.

Just sayin'

Jim

GREAT advice!!!

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When I had my house upped to a 200 Amp service and a separate 100 Amp service put in my garage there was already a single 12/2 run out to the garage that ran two 4 ft florescent lights and two outlets on its own 20 amp breaker in the house that I chose to leave in place for the alternative/backup power to the garage. It’s come in handy a couple times when I’ve shut the subpanel breaker off in the house while doing other garage wiring. But then again, it wasn’t a planned action just taking advantage of what was already there.

Oh, I did dig my own trench and bury my own conduit (about 80 ft distance) but had the electrician run the wires through the conduit. And another thing that I decided to do was to bury a separate conduit for a run of internet and cable to the garage at the same time (you can't run these with the power run), something that some others may want to consider. I had used my wireless link on my PC a couple time in the garage with so so results, having a direct link really makes a big difference. Just some other things to consider if you’re going to run your own conduit, a second/separate conduit could come in handy. Scott...

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With the cost of copper wire and the cost of material, the $1300 bid is a bargain.

When you figure the cost of three legs of wire, ( two hots and a neutral), plus a ground wire running back to the main panel, that is a cheap price. There should be a ground run back to the main as part of the N.E.C.

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