Call a licensed electrician before you burn down your new addition.

I’m an industrial electrician.

I can manage to not burn down my house. At the mill I would put in a box speced for the environment with a terminal strip.

Things are done different in residential, But the basics are the same.

I have a solution, that will be sound snd safe. Just wondering how this is normally done.

There are wire connectors (example) designed for this purpose. Polaris makes screw-down connectors -- but they are expensive. I've bought three to extend a 6/3 range circuit but haven't used them yet.

(A common reply to any wiring question here is, "Hire an electrician! You're going to burn down your house!!!")

As long as the boxes are accessible, have covers, and don't exceed the maximum fill requirements, you should be fine.

Is this the right track?

You are on the train, but you need a conductor to drive it (a licensed electrician). You can tell by how you say things: "5 gang" switch box as junction box, no "homerun," "support wires as enter and leave" but attics require more protection, many nuances in NEC re SABC/MWBC, fill requirements, etc. Hire an electrician for this, then you can see how he does it and combine that with your present knowledge for future projects on your own. It may ruffle your feathers to admit it, but sometimes you just don't know what you don't know, it's not a bad thing to say that.

Regardless of who does this, I wouldn't put lights on the same circuits as outlets, and all outlets must be GFCI protected, either as a group or individually. Are the walls around your existing outlets open, so you could just run a cable to the new ones (without a junction box)?

If you’re not a licensed master electrician in all 59 states and Hawaii, you need to get one to add that outlet for you or you’ll die a horrible death and catch your house on fire..

call us at

PROfessional EElectrical and Used Cars BR 549.

Seriously, when all you master EElectrishans can tell me how to use brass as an insulator, I’ll listen to your scarey storied.

BTW I have used brass as an insulator, sent a Mega watt of power down the circuit. some people do it all the time.

BTW Again.

a warm thank you to those who were actually helpful.

Whenever I work with a 240 volt circuit I always refer to the Estonian electric code figuring the Estonians have more familiarity with higher voltages. I consult the Venezuelan code for low, "brownout" voltages.

My neighbor is a licensed commercial electrician and he is fully conversant with residential work practices and requirements. I have an in-law who is in charge of the electrical department of the entire court system for a major metropolitan city; he’s fully knowledgeable about residential electrical code and practices. And, though I’m not a licensed electrician, I’ve wired and rewired various houses, and always passed inspection the first time. The apparent disconnect between the OP’s stated credentials and basic, residential electrical knowledge has me puzzled.