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I'm doing a major kitchen and bathroom remodel project and decided the old federal pacific breaker box needs to be replaced. Since I'll be rewiring the bath and kitchen, I figured it makes sense to plan to eventually rewire the entire house.

I made a spreadsheet with all of the current and future loads I may add to the house then sectioned them off into different branch circuits with the type of breaker that will protect them. Would someone mind taking a look at my planned-out wiring and let me know if it looks correct or if I'm missing something obvious? I hope to get some feedback about best practices for planning house circuits and what methods are needed to protect them, using NEC 2014 for reference (I live in Portland, OR).

Some additional information relating specifically to my project:

  • My house was built in 1956
  • Most of the wiring is NC fabric-coated wire. Some of it is romex
  • The old house panel is a 100A sub panel, fed by a 200A main panel in the detached garage
  • I plan to replace the house panel with a 16 or 20 slot 100A panel (is one or the other better?)
  • If there are any AFCI and GFCI combination requirements, the main breaker will be AFCI and any outlets on that branch will be GFCI outlets
  • I plan on driving in two new grounding rods at the sub panel and bond them to the water main (house is getting re plumbed with pex) and gas pipes
  • Does this sub panel need a grounding wire connected to the main panel in the garage?

Here is my spreadsheet:

based on feedback, here's an updated plan:

Updated!! v2 circuit plan

  • Depending on jurisdiction, he doesn't neccessarily require an electrician to sign off on the work, but he likely requires at least a permit. Professional advice, for a project of this complexity (and potential hazard) is a good idea, but it may not be required. – Johnny May 12 '16 at 22:25
  • You have all 20amp breakers listed on your spreadsheet. Are all of these branch circuits wired with 12 gauge wire? Also your knowledge of grounding where more is better is wrong. There are specific codes that address this. You must feed the sub-panel with 4 conductors, you should not bond additional grounding at that point. Watch out for ground loops. – Tyson May 12 '16 at 22:52
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    @Sparky256, this is not at all true in most areas. And the part about the fire marshal is an old school fire and brimstone wives tale. ......+1 for balance. – Speedy Petey May 12 '16 at 23:16
  • @Tyson, ground loops are not really an issue with residential dwelling wiring. It's not like he's wiring a sound studio. – Speedy Petey May 12 '16 at 23:18
  • Thanks all. @Tester101 -Ed, below, mentioned the same. I will make sure to have two dedicated outlet branches for the kitchen. Exactly the kind of feedback I was looking for. – tbox May 12 '16 at 23:30
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That Federal Pacific panel has to go as they are dangerous. As far as concerns about your skill, you sound like that particular kind of newbie who is well capable of learning to do it all safely and well; however my hunch is you are still thinking too much, and need to read a little more. It's OK, we all start there.

Normally, just replacing a sub panel is a straightforward thing. Change panel, reattach wires, done. However, this is only part of a project with a much larger scope. You must contemplate (i.e. ask your permitting authority) whether you have crossed the legal threshold of a remodel. If you have, everything in-scope must be done to all current codes. Even ADA!

The 2-circuit requirement for kitchen outlets is not intended to mean "1 circuit for this wall, 1 circuit for the other wall". I'd encourage some more research but if it was me, I'd interleave the outlets, every other outlet on a different circuit. Also there's nothing wrong with more than 2 outlet circuits in a kitchen, the whole point is to prevent trips when the chef is madly at work, so the chef isn't hobbled with limitations like having to put the toaster here and the George Foreman over there, and avert ugly workarounds like extension cords draped across sinks or stoves, etc.

I see you plan to go 12 AWG wire for almost everything (that's what 20A breakers mean) - that's awesome. Feel free to kick the refrigerator and smoke detector up to 12AWG also - that way you don't have to buy any 14AWG wire. I don't own any! If you have some other reason to use a 15A breaker you are welcome to use that on a circuit wired in 12AWG.

You may want to run the water heater circuit in 10/2 or even 8/2. That will allow you to easily upgrade to an electric water heater in the future. Still use a 15A or 20A breaker because the outlet is still only good for 20A. There is a trick to fitting 8+ AWG wire on a 15-20A outlet, just ask.

I would go with a much larger panel. You have either -1 or 3 circuits left, and that's too little headroom for my comfort. Getting a larger panel is dirt cheap compared to the cost of replacing perfectly good breakers with duplex breakers (I call them double-stuff) merely to shoehorn everything in. Also, larger panels in combo-packs come with more breakers and that is far-and-away the cheapest way to buy breakers. Another reason to avoid duplex breakers is if you ever need AFCI, GFCI or whatever future thing comes out - those are much more expensive in duplex breakers because of the miniaturization required. Don't think you must use a 100A panel - you can use a larger panel (200A), you just can't use a smaller one (70A).

Remember each sub-panel must have its neutral bus bar separate and isolated from its ground bar. That means removing bond straps, magic green screws, neutral bar kits, whatever the panel requires to do that. You might consider a panel with a neutral and ground bar on each side of the panel. That's a convenient feature so wires don't have to cross over the panel.

Keep in mind how your house got a dangerous Federal Pacific panel. The last guy bought cheap. Feel free to research the good-better-best that each manufacturer offers, the price differential for "best" is quite small compared to the overall cost of a remodel. You may find better selection and better prices at a real electrical supply house.

There is nothing wrong with more ground rods. Go nuts. The key is that all the grounds are connected to each other by wire - and they are not connected to neutral anywhere except one place - the main service panel.

  • I have not seen duplex/quadruplex GFCI/AFCI breakers yet -- and when I asked Eaton about 'em, they weren't in the cards from what I was told. Also, re: ADA -- "universal access benefits everyone". (As a simple example from the commercial space -- being able to use a barrier-free water fountain while your hands are full chuckles.) – ThreePhaseEel May 13 '16 at 3:44
  • Thank you for the great insight. You're right, I'm a total noob at this and if it were my choice, I'd leave the electrical to a pro. Unfortunately I can't afford it. Not only that, I love to learn and have always wanted to know more about electrical work so this seemed like a good opportunity. Saying I up to a 150A sub panel, can I keep the existing conductor from the main panel? The sub panel is fed by a 100A breaker in the main panel. Thanks for the water heater recommendation... That should be an easy upgrade. I'll also just run full 12AWG (had this originally in the plans) – tbox May 13 '16 at 4:42
  • Also! Good info on the kitchen circuit. That makes sense. I was mainly planning it based upon ease of install. My kitchen is quite small which is why I have just the 2 circuits for the outlets. Can I get your opinion on the number of outlets I have listed for each of those and if you think it's enough (circuits 14 and 16)? I suppose if I'm going to go with a 150 or 175A panel, adding another branch would be pretty trivial. I just feel like I'd kinda be wasting wire/breakers if I don't really need to. – tbox May 13 '16 at 4:49
  • Yeah, you can use any size panel you like, as long it is 100A or more, and you can use the old wire run. The breaker in the main panel must be the lesser of what the sub-panel allows and what the wire from main to sub-panel allows. I'd hit up a bookstore or HD/Lowes, check out their books and find one that speaks to you and devour it. Beware library books as they tend to be old, and there have been big code changes recently. You really want to take note of the code stuff e.g. around kitchens. – Harper May 13 '16 at 4:49
  • Kitchen outlets totally depend on the peculiar geometry of the kitchen. Those rules are fairly picayune and I can't guess without seeing a layout. But the books will tell you. The rules seem arbitrary but do eventually make sense if you work with them enough. – Harper May 13 '16 at 5:03
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I am a licensed Oregon electrician and it IS 100% legal to do your own wiring including planning. It needs to meet code or it will not pass inspection. First I would never update to a new panel for a home with a 100A even as a sub. I would put in at least a 150A panel with more breakers, the cost difference is not that big. 100A is the minimum size allowed by code so it is legal. After a quick look, you need 2 20A circuits for counter top appliances in the kitchen these can have no other loads (with the exception of a clock outlet & an A gas range igniter outlet). You will need tamper resistant outlets in all areas below 5-1/2'. I am not aware of a 240V AFCI and you have one listed for the dryer. To my knowledge only 120v AFCI protection is required. You should install a outlet close to the water heater because in the future it looks like we wont have pilot lite water heaters available. The garbage disposal dishwasher afci/gfci not a good idea ORS918 table 1E gfci not required for dishwasher , also GFCI AFCI not required on equipment known to have problems with these. Garbage disposals wipe them out regularly. Maybe I missed it but I don't see a refrigerator, freezer outlets. The Oregon exception for GFCI on these is behind equipment not easily moved. Stoves, refrigerator, freezer, built in microwave, dishwasher are all examples where they are not required in Oregon. You listed porch lights there will need to be a GFCI outlet at each porch (outside). That's a quick first Pass it always is a good idea to get a review. I will look it over again later just in case I spot something I missed. Good luck and be safe.

  • Thank you @Ed Beal. I was wondering about the GFCI requirements. Good to know I don't need them behind "not easily movable" appliances. I thought since they weren't hardwired they were required. The water heater is a tankless gas heater so I can easily change that to a single outlet instead of hard wire. – tbox May 12 '16 at 23:32
  • My mistake on the 240V AFCI--that will just be a regular 30A breaker. I will also leave out AFCI/GFCI for the dishwasher/disposal. And yes, I totally forgot the refrigerator... that doesn't need a dedicated circuit does it? I also forgot to add in a circuit for hardwired fire/co2 alarms. So you would recommend going to a 150A panel instead? Does that mean I'd have to run new conductor from the main 200A panel to the house? I don't know if that would be worth it for me. It's a small house and what I have listed is probably the max I could ever add to the house. – tbox May 12 '16 at 23:42
  • There are two-pole AFCIs out there but they only go to 20A. – ThreePhaseEel May 13 '16 at 0:19
  • Since this is a sub you could put in a larger panel with the feeder wiring sized to the breaker in most areas I have worked in Oregon. With the AFCI the breakers cost $ and I am sure 1/2 are way expensive if they exist I have not looked or purchased a 1/2" AFCI but the few 1/2" GFCI's that I did buy almost caused my brother heart failure! – Ed Beal May 13 '16 at 0:46
  • I did just update my spreadsheet image with revised circuits. I added the second circuit to the kitchen and, after looking through the code, found I could actually add my gas range to one of the circuits. I also noticed the dining room and pantry must belong to these two separate circuits so I made sure that abides to code as well. – tbox May 13 '16 at 0:50
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Does this sub panel need a grounding wire connected to the main panel in the garage?

Yes, you need a 4 wire connection (2 legs hot, neutral, and ground) from the main to the sub panel. Also the sub needs to be grounded, as you have planned two ground rods you are all set there.

I agree with Ed Beal that in the case of electrical panels, bigger is better. At least more circuits is better. You asked if the wire feeding the house would need to be upsized if you went with a bigger panel at the house. The answer is, no. If you have a 100 amp breaker feeding the house now with wire rated for 100 amps then that can all stay the same, if you wish. You can then buy your choice of >=100 amp panels to use in the house. For instance another 200 amp 40 circuit panel could be used. The rating of the sub-panel can be higher than what it is fed with. It just can't be lower. You also don't need a main breaker at the house unless you want one, or you locality requires it. So, you can install a main-lug-only panel if you wish.

So, that being said, if you want to plan for future expansion install a 24 circuit or greater panel. Such as this one.

Otherwise, you have a very well thought out methodical approach here that should lead to a superior installation. Not bad for a DIYer.

Good luck!

  • Thanks, I will go the bigger panel route. Seems to be the consensus. I have to double check, but one of the electrical bids I got, the electrician thought they hadn't run a ground from the main panel to the sub. He wasn't 100% sure because he didn't thoroughly check it--I hope he's wrong! Replacing that wire would be a big pain in the butt. At least if that's the case, I can run a thicker gauge to the sub in case things change in the future. – tbox May 13 '16 at 15:49
  • Oh, one more thing on panels. Many are labeled as (for instance) 32 circuit 16 space. That means it takes 16 normal breakers and 32 duplex "double stuff" breakers. Those are more expensive and often not available in GFCI or AFCI. Don't be fooled. Until recently, the legal limit was 42 space. – Harper May 13 '16 at 18:41
  • In existing installations there is an exception to continue to have a 3 wire connection from the main to the sub. It is contained in 250.32(B). There are three requirements but it is too wordy to quote here. But paraphrased, you don't have a ground wire, you don't have any metallic pathways between the buildings (things like gas lines or metal water lines), and you don't have GFPE upstream (this is for commercial/industrial). – ArchonOSX May 14 '16 at 8:54
  • @ArchonOSX looking at the main panel yesterday, I noticed there's a bare ground that's bundled with the load conductors heading to the house and sub panel, but at the house there is no ground entering the panel. There is another 60A sub panel for a hot tub (which is being removed) that also has a ground wire running to it. This sub panel does have the grounding wire all the way to the sub panel and is connected to ground and the neutrals and ground busses are separate from one another. Any clue why there would be a bare ground running with the 3 loads to the house but no connection there? – tbox May 15 '16 at 1:56
  • Sounds like someone either bonded it to the panel with a bond bushing or just cut it off. That would be a mistake. Connect the neutral bar to the panel at the house with a small wire. Then disconnect the ground and neutral at the garage and test for continuity between the neutral and ground that go to the house. If they just cut it off you won't get continuity. – ArchonOSX May 15 '16 at 16:40

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