Hey guys! I have been a long time FHB podcast listener and been reading as many articles as I can as I am planning a new home build in a few years and been trying to think of every which way I can to build a “future proof” (i.e. highly maintainable/repairable home) and I have currently been turning my eye towards electrical works. I know I want to support 20a throughout the home and would like each room to have its own breaker. Recently I have had the thought of running a single electrical cable to each room using a gauge rated for continuous 20a connection (12AWG?) and then adding a ceiling mounted junction box to this split the cable so each power outlet (12AWG) and light switch can then be and light switch (16-18AWG) can have its own cable. This would result in more cable usage throughout the project, however, it would make it would result in multiple benefits: 1. Cables are easier to repair and replace if ever needed. 2. Power draw over multiple outlets wouldn’t heat cables as much as power requirements increases over the years. Am I overlooking anything? Is the additional connections via the junction box an additional hazard that out weights the possible benefits?
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You cannot use 14 gauge wire anywhere on a 20A circuit. You cannot use anything smaller than 14 in a residential electrical installation. Almost all residential circuits are required to have arc fault interruption protection. Heating cables is not an issue. Cables are never easy to replace. LED lighting has reduced many residential loads. With the price of copper as high as it is extra cable could easily be very expensive. Your junction boxes would be very hard to conceal.
You could consider a 20A 2 circuit sub panel in each room, fed by 12/3 wire and equipped with 2 15A AFCI breakers. AFCI breakers are expensive. Ideal placement of this panel would be problematic since your inspector might not want it in a closet. You should definitely consider a sub panel for your kitchen/dr/family room.
Ok, I updated my post just for clarity sake. I was hoping that having a junction box in the ceiling of each room, with a service panel for inspection/maintenance, and then feed all of the outlets from there would allow fairly easy cable replacement, as they would all be direct pulls so as long as the cable wasn't severed in a way it can't be used to pull a new wire it should be easy because of relatively short distance and minimal bends (less than 3 in almost all situations) it should be easy. I am planning on having conduit feed the electrical cable up the wall and have that conduit end once it reaches the ceiling for the same reason. I am not particularly worried about the cost as much as the long term serviceability and to a extend the looks of the solution.
Cables in walls must be secured, This is what staples are for. You can't pull them or use them to pull new ones.
16 or 18 awg is really a no-no.
And keep in mind that there is something to be said for a lighting circuit separate from outlets.
Conduits and cable chases are good for chasing cable as they may develop, but keep in mind that you also want to avoid paths for fire and smoke to follow.
yeah, I figured for lighting only wires it would be perfect, but honestly there really isn't too much of an actual difference (price wise) running that with 12 AWG and gives me some flexability if for some reason I ended up having to split a cable off of that lead or something.
I’m a homeowner (not an electrician) and have been rewiring my house for the past year, including a full kitchen remodel.
I’d recommend you get “Wiring a House” by Rex Cauldwell. It’s excellent, with useable, practical advice. But it’s dated when it comes to code. Do your homework on the latest code requirements. He doesn’t cover wiring diagrams that builders use, but it’s covered in “Remodeling a Kitchen” by Sam Clark. Maybe better is “Renovation: 5th Edition” by Lichfield and Harley. I found diagrams to be very helpful before doing any work.
Also there are great youtube channels by electricians. Off the top of my head is “Electrician U” (or something like that).
Go talk to your local code enforcer. I went to my local officer and she offered to come to my house to offer guidance before I got to work.
I will say this, trying to plan your wiring to adapt to a mysterious future may be an exercise in futility, unless you are willing to surface mount every outlet and run MC cable.
Hopefully by the time you get started, wire wont cost as much as it does right now!
Yeah, I am just a young(er) guy who works in IT who is planning to build his dream/forever home in the next few years and trying to take advantage of any/all ideas to make any future upgrades just a little bit easier. I know no matter how hard I try i'll never think of everything, but if I can prevent even 1 situation where I have to gut a room or two to make some changes/repairs, I think the time spent is worth it. I'll check out those books :D I just got started on the BS & Beer podcast so binging that atm.
Running your Lighting and RECPTACLES together is a bad idea. If you have to work on the receptacles YOU HAVE NO LIGHT and if you have work on the lights, YOU CAN'T PLUG IN ANYTHING (LIKE ANOTHER LIGHT) to work on it. You should be able to wire most NORMAL BEDROOMS 2 or 3 on one breaker. The rule of thumb is 1.5 amps per receptacle which gives you 12 outlets per 20 amp breaker but, as I understand it, that isn't written in the code and you can actually have more receptacles than that on one breaker. What matters is what LOAD you will be putting on the breaker not how many receptacles are attached to it. So in a bedroom where everything is a small load due to LED bulbs in Lamps and more efficient electronics, there isnt likely to be 1.5 amps (or 1500 watts) being drawn on any particluar receptacle unless you have one where you figure a hair dryer will be attached. As mentioned above, receptacles now mostly have to be coverd by Arc Fault and many times Ground fault as well so most are using dual function breakers which are right now $60 per and heading up thanks to Brandon. If you combined more rooms on 1 breaker you save $60 per breaker.
You could bring each room back to a junction box in say a basement and then if you want to ever put a room on its own breaker you only need to open that box and home run a cable back to the panel. So you home run the first bedroom to the panel. Daisy chain the receptacles in that room and daisy chain to a junction box and join there the second room and so on. Then if you ever need to break off any of the bedrooms all you do is go to the appropriate J box and disconnect the preceeding room and connect a new home run back to the panel.