Running 115VAC in the Garage

[ADKGarage]

Recently I have completed the build of my detached, non-commercial garage in the Adirondaks of New York. 100 amp service has been completed to it and is terminated in a breaker panel. So far everything is good as per an electrical inspector who gave his okay. Now I would like to complete the running of 115V throughout, outlets and lighting. The walls will be insulated and finished with sheet rock. Can you guys throw me some suggestions to do this or would I be better off to let an electrician come in and do it and bite the bullet cost wise, as I have the time to do this myself. If there is an already compiled writeup, please direct me there.

1) Can I use plastic outlet boxes, they are larger than metal and I prefer them.

2) I am also running 2 separate circuits with outlets 4' high and separated by 8 feet. This way, every 4 feet I have an outlet. I'm tired of looking for outlets, I want plenty. There will be 7 outlets per circuit.

3) I'm using 12-2 romex, 20 amp circuits, can you give me the particulars in running and securing the wire to the studs.

4) On the ceiling, I am running 14-2 romex for 3 separate circuits, each with 4 fixtures (T-8 4 bulb). Each one receiving an outlet that I can plug the fixtures into. Each will draw less that 2 amps.

5) I will also have a 30 amp circuit dedicated to my welder. Any thing I should consider in running/securing the circuit/outlet?

 

[pattenp]

For the wall outlets you bore holes in the center of the studs and run the wire straight from box to box and secure the wire within 12" of the box with a staple. Use protector plate on the stud over every point where the wire passes through a stud. Or you can run the wire from the top of the wall down through a bored hole in the top plate securing the wire to the side of the stud with staples then from the box back up the stud through the top plate then over to the next outlet and down again. The up and down route will use more wire.

 

[Zeke]

Some will say (including me) that plastic boxes flex more when used to house receptacles and when plugs are constantly inserted and pulled out. If you want more room, buy deep boxes or use 4" boxes with plaster rings.

Given the amount of boxes you plan on buying, check out a case price at the local electrical supply.

 

[Highbeam]

As I recall, you only need to put a protector metal plate over the bore hole if the edge of the hole is closer than 1.25" to the face of the stud. So center your bore holes and keep them small to avoid all the nail plates.

All garage receptacles must be GFCI protected. There are a few ways to do this but I like to use a single GFCI receptacle which will protect up to 8 downstream outlets.

Put the boxes in so that the top of the box will be exactly 48.5" from the floor. This way you can mount sheetrock or OSB sheets 0.5" off the floor and the top of the box will not require you to cut out the next sheet above.

 

[tylernt]

1. I dunno about local NY codes but plastic is fine per the NEC.

2./3. I think code requires GFCI outlets even for detached garages now, so what you'll do is run 12-2 from the breaker to the nearest wall box and install a GFCI receptacle there. Connect the incoming power to LINE and then run another cable from the LOAD terminals to the next box. Now just put a regular receptacle (which is GF protected by the upstream outlet) in the next box. Each receptacle should have two hot screws and two neutral screws, so you can make the connection for the next box down the line. Never put two wires under one screw. Do not use "back-stab" connections! (Screw clamps are okay.) Since this is a detached garage, tamper-resistant receptacles are not required.

The jacket of the Romex should only protrude into your boxes 1/2" or so. Leave 6" free length on the individual wires.

Pick up a pack of "greenie" wire nuts. They have a hole in the top. At each switch or receptacle, leave one of the ground wires long (12") and cut the rest to the standard 6". The long ground will stick out the top of your greenie 6" and attach to the green screw on the switch or receptacle. If you have more than one switch or receptacle in a box, it's acceptable to use that one long ground wire to run continuously from device to device wrapping around all the green screws.

4. On a 15A breaker, sure. Don't think you'll need 3 separate circuits though -- you can run a single 14ga / 15A circuit up to 12A continuous or 1,440 watts. Although two circuits might be nice in case you trip a breaker, so only half the lights go out and you're not plunged into darkness. The switch should be the first thing your cable from the breaker runs to, then from the switch you can go up to the lights.

You can have multiple circuits coming into one box with multiple switches, but keep the neutrals separate (don't nut them all together). You should, however, combine all the grounds together.

5. How far from the panel? 10ga wire would normally be used but if it's a bit distant you may want to use 8ga. Also, consider using 3-conductor cable: black, red, white (and green/bare ground). You may not need the extra conductor now, but it's sure nice to have it for future flexibility for a new welder. You'll use a double-gang box for this receptacle, of course.

 

[theoldwizard1]

Use 12 gauge wire and 20A breakers for wall plugs. 14 gauge and 15A is fine for lighting.

Stop by HD. They have some good books on basic wiring.

 

[pattenp]

True, but I suggested the plates because it's cheap insurance.

As I recall, you only need to put a protector metal plate over the bore hole if the edge of the hole is closer than 1.25" to the face of the stud. So center your bore holes and keep them small to avoid all the nail plates.

 

[bczygan]

It may seem obvious, but I always like to remind myself that more "convenience" outlets does not mean more available power, just more convenient locations.

 

[tylernt]

It may seem obvious, but I always like to remind myself that more "convenience" outlets does not mean more available power, just more convenient locations.

True, but if you're the only one out there, you can only run so many tools at once. It's usually when you have other people working at the same time that the issues start...

 

[porschedude996TT]

True, but I suggested the plates because it's cheap insurance.

Case in point, what if you had one long screw in the box of 1-1/4" drywall screws...

Or someone hangs a picture with a 16 penny nail...


It is cheap insurance.

I have 13 receptacles on each of my 20amp convinence circuits. One of them is against a wall that most of my heavier load tools are used and I ran 10 gage wire.

 

[Charles (in GA)]

Use deep 4x4 metal boxes with mounting brackets and mud rings, even if only one receptacle, you will appreciate the extra space.

The pic below is a little extreme on the mounting for a 120v receptacle but you get the idea, good solid mounting even if you only used the side bracket, but the wood helps alot. large box is great, lots of room to work in, room for a gfci, etc.

Charles

 

[kenfath]

I'm of the opinion GFCI recepticles are fine, **** I prefer GFCI breakers. WHY? Main reason is all of the resets are in one place. You may know where the GFCI recepticles are located in a multiple recepticle circuit -- will the next person? The way I understand the NEC is the ceiling recepticles also need to be GFCI protected. I just can't see trying to instruct the wife when I'm out of town to get the 12-foot ladder and push the button on the ceiling GFCI.

My preference is to use metal boxes. The standard depth 4x4" boxes with drywall rings easily accomodate a 12-2 w/ground NMC in and out. I use the deeper boxes when three or more NMCs connect to a box. While most plastic boxes work fine, my experience is there is one or two that for whatever reason (wornout cheap builder-special recepticles and/or switches is one reason) are opened with some frequency and
result in the screw threads being stripped. Other preference is use 12-gauge wire throughout the project with 20AMP GFCI breakers. Yes, your plan is adequate and will do the job; and my suggestions cost a little more, but some things are worth it.

Last suggestion is to place a 3/4 or 1-inch flexible metal conduit from the top of the panel, through the top plate and ending a sufficient distance so you could access it for additional circuits you will someday want to add.

 

[Norcal]

When using 4 square boxes & raised rings use ones that are 1/8" deeper then the wall finish material, for example w/ 1/2" drywall, use a 5/8" ring and if 5/8" drywall use a 3/4" one & so on.

 

[ADKGarage]

Thanks guys, you just helped me out a lot and more than answered my question. I assume that the wire I run into the breaker panel should also be stapled within 6 to 12 inches also. Would that be correct?

Once this is done, I'll see how long it takes for the inspector guy to get to my place and give his okay. My friend waited better than a month. I hope to get this done sooner than that. Thanks again!

 

[Zeke]

Yes, you do attach the wire at both ends and at 4' intervals when not threaded through framing, e.g., across the tops of joists, or truss chords, on runners.