What wire to use instead of Romex

Both panels were put in to replace the original panel which did not have enough room for another breaker for my NEMA 14-50 outlet for my EV charger. A single larger panel would not fit in between the panel of one of my neighbor’s to the right and the house panel (power for common elements) to the left. I had to go to Home Depot earlier today. While I was there, I did in fact pick up a Homeline breaker to have on hand (20 AMP, single pole).

Is the wall in the condo wood studs with drywall?

Yes - wood studs with drywall. Constructed circa 1973/1974.

Is the new wall outlet in the Condo, on the same common wall with the garage? 

Yes. It's a short, straight run from the outlet down to the garage - just as it appears in the illustration I created above.

@jea48 

Best Practices:

It's recommended to use separate, appropriately sized 20 amp circuits with their own breakers and wiring to feed each half of the duplex receptacle. This ensures proper protection and avoids potential hazards.

Proper Method:

1. Separate Circuits:

Each 20 amp circuit should be run from its own 20 amp breaker in the electrical panel to its respective half of the duplex receptacle.

2. Appropriate Wiring:

Use 12 gauge Romex for both circuits, as it is rated for 20 amps.

3. Proper Termination:

Ensure the hot (black), neutral (white), and ground (bare or green) wires are correctly connected to their respective terminals on each half of the duplex receptacle. 
This is code ! 
 

Cheers 

@1971gto455ho 

It's recommended to use separate, appropriately sized 20 amp circuits with their own breakers and wiring to feed each half of the duplex receptacle.

I never thought about doing two runs to one duplex outlet. That's really kickin' it up a notch! I'm going to consider doing that. FYIW: My plan was to plug my stereo power amp directly into one outlet (manufacturer recommends NOT using any type of power conditioner) and my power conditioner into the other, which will have my preamp, DAC and streamer plugged into it.

@roccity  

Using appropriate wiring and breakers on a split duplex has been around for years and it is most definitely code and designed to be used that way as well. It is essentially no different than using a single outlet on a duplex box. Wiring must be done properly and you have absolutely no issues with safety. 
I did this because each one of my amps requires its own 20 amp breaker and I wanted to minimize dry wall and stud issues. The changes are well indicated in the panel and in the duplex box so any future people opening either will realize that multiple breakers have to be turned off. 
 Chreers

@1971gto455ho Said:

Best Practices:

It’s recommended to use separate, appropriately sized 20 amp circuits with their own breakers and wiring to feed each half of the duplex receptacle. This ensures proper protection and avoids potential hazards.

Proper Method:

1. Separate Circuits:

Each 20 amp circuit should be run from its own 20 amp breaker in the electrical panel to its respective half of the duplex receptacle.

2. Appropriate Wiring:

Use 12 gauge Romex for both circuits, as it is rated for 20 amps.

3. Proper Termination:

Ensure the hot (black), neutral (white), and ground (bare or green) wires are correctly connected to their respective terminals on each half of the duplex receptacle. 
This is code ! 

This is code ! 

No it is not. I posted word for word from the 2020 NEC code book.

I will look tomorrow for when NEC 210.7 Multiple Branch Circuits, the code edition year it was added to the NEC code book.  You may have wired your outlets the way you have them before 210.7 Multiple Branch Circuits was added to the NEC. 

Best practices is no guarantee that it follows or meets NEC or AHJ code. 

Your quoted material might be old. It should be updated to meet current NEC code. Or at least for the NEC code edition your state is still using. 

Please post the Website for the quoted material in your post. 

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