Rewire outlet circuit: Location of outlets, wire run alternatives, GFCI best practice, and outlet spacing

Question

I am rewiring a circuit. This circuit is a mix of knob and tube and older Romex. It only has a hot and neutral, so no dedicated ground. However, the outlets are three-pronged. There is no GFCI on the circuit. I want to fix all that by running everything new from the breaker box.

1. Location of outlets. This is an old house with lath and plaster. There is a large (12") baseboard and the outlets are in it (so maybe 4" above the floor). Can I replace the wiring on these without relocating the outlets? If I want to add additional outlets, can I also place them at the same low level to the ground?

2. Circuit routing. Circuits typically daisy-chain their outlets with line going in and load going out for all but the last outlet. However, I have easy access in the basement. Instead, I am considering in the basement, at every outlet, add a box. This box would take in the line and have two loads...one up to the specific outlet and the other to the rest of the circuit. Is there any reason not to do this? It seems it makes the install easier and if another leg were to be added in the future (no plans to do so), then it would make that easier also. Downside would be some additional cost of materials.

3. GFCIs. What is best practice? Should I prefer a breaker with GFCI built in, a GFCI on the first outlet, or a GFCI on every outlet. I'm curious what is "good" and what is "best" to do.

4. The spacing between outlets is quite wide. Because I'm rewiring the circuit, do I need to add additional outlets to pass inspection?

Thank you for your advice.

Answer 1

I have never seen any requirements as far as the minimum height of electrical outlets, they can even be installed on the floor. Routing your cables through junction boxes and pigtailing to the outlet above and to the next outlet is OK but remember that those junction boxes must always remain accessible so think twice about it if you ever plan on finishing the basement.

If you're protecting all the outlets, one GFCI at the first outlet and the rest off the load terminals of that GFCI is the least expensive, The breaker GFCI's can be rather expensive. You might also be required to install arc fault breakers.

The spacing between breakers could be a concern. The US National Electrical Code, Section 210.52, states that there should be an electrical outlet at least every twelve feet measured along the floor line.

Answer 2

1. Height is fine. While there's a lot of "developed convention" in putting them 16-18" above the floor, actual code is within 18" (?) of the wall in the floor to less than 5'6" (?) off the floor, without going and looking it up. So the precise numbers may differ, but the general idea is conveyed correctly here.
2. Other than cost, the second downside is "more points of failure" (every outlet involves a junction apart from the outlet) but there's nothing against it in code, so just do good work on the junctions so they won't be a problem later.
3. Unless you are going to manage to interact with the insulated wires between the breaker box and the first outlet, (and you'll have to modify your approach to item 2 at the first outlet) there's no functional difference. GFCI breakers usually cost more. Some folks like that you can find all the GFCIs at the breaker box, others don't like the trip to the breaker box if one trips. It's a wash. Pick one and go with it. Every outlet is expensive and needless, but does mean the one that tripped is right where you plugged in.
4. 12 feet between is code minimum, with some additional complications (12 feet is for unbroken wall. Each section of wall over 2 feet needs one, unless it's behind a door (when the door opens.) More outlets than code requires on that long unbroken wall is sometimes/often good, depending.)

Answer 3

Nothing in Code requires outlets be a string. Code requires a "tree" topology, so you can have tee's anywhere you want, even right on top of each other. The only limitation is "box fill" re: number of wires and devices vs the box cubic inches.

Better "spec grade" receptacles and switches ($3) and GFCI receptacles accept 2 wires under each screw. So you don't even need wire-nuts to support a double-Tee, with 1 supply connection and 3 onward connections.

Also, each junction box you create must remain accessible forever, without removing finish materials from the building. So it can't be drywalled or mudded over, and you must be able to access the box cover and restore the building to as-found without using any tools. It can be behind a cabinet door, or in the back of a bookshelf concealed by books, or above a drop ceiling if the panels just lift out.